The Seeds of Doom ( TV story ) The Seeds of Doom was the sixth and final story of season 13 of " Doctor Who " . It marked the Doctor ' s final major involvement with UNIT until " Battlefield " in season 26 . It is also the first televised UNIT story in which neither the Brigadier nor Benton appears , with the Brigadier unable to help as he was " in Geneva " . It was director Douglas Camfield ' s last involvement with the show . It was originally intended for " The Hand of Fear " to be the finale , but the scripts were not ready in time , so " The Seeds of Doom " filled the gap . Colour Separation Overlay , or CSO effects , were to be used in " The Hand of Fear " . These were best achieved with Outside Broadcast ( OB ) videotape . After " The Hand of Fear " s delay , " The Seeds of Doom " inherited the booking for OB tape . This allowed the story to feature an unusually large creature . Synopsis . When scientists in the Antarctic uncover two mysterious seed pods , the Doctor is called in to investigate . He soon realises they are extraterrestrial and extremely dangerous . At the same time , however , ruthless plant - lover Harrison Chase has learned of the find and decides he must have the pods for his collection of rare and beautiful flora . And the pods themselves harbour intelligent life with sinister plans of its own . . . Plot . Part one . Somewhere in Antarctica , scientists Charles Winlett and Derek Moberley discover an egg - shaped object in the ninth layer of the permafrost and take it back to their camp . John Stevenson , the base botanist , identifies it as vegetable - based and estimates it has been buried in the ice for some 20 , 000 years . Winlett thinks it looks tropical , like a gourd , but Moberley points out that Antarctica had ceased to be tropical at the time this was buried . Stevenson claims he feels something odd about the pod , as if it is alive , but the others dismiss this . Back in London , Richard Dunbar of the World Ecology Bureau tries to show the Doctor photographs of the pod . Although he feels that the Doctor cannot help them , his superior , Sir Colin Thackeray , insisted . The Doctor examines the pictures and asks if they had considered the idea that the pod is extraterrestrial . He tells Dunbar to contact the expedition by their regular video link and tell them not to touch it until he arrives . Back at the base , Stevenson discovers that the pod is growing larger , and he believes it is absorbing ultraviolet radiation . Winlett reminds Stevenson that London ' s orders are to leave it alone until the Doctor arrives tomorrow , but Stevenson thinks the Doctor is just some crank Thackeray is foisting on them . He feels it is their discovery and they can do what they want with it . In England , Dunbar visits the estate of millionaire Harrison Chase . Chase ' s estate is filled with thousands of plants , and he considers it his mission to protect the plant life of Mother Earth . Dunbar has come to show him pictures of the pod and its possible extraterrestrial origin , and he hints that such a valuable specimen could easily disappear . . . for a price . Chase wants to know the precise location it was found , and Dunbar gives it to him . Chase calls for one of his men , Scorby , and gives him an assignment , telling him to take Keeler along . At the base , Winlett is half asleep near the pod . The pod opens up and a frond - like tentacle whips out and stings his arm , causing Winlett to collapse in pain . When Stevenson and Moberly find him , Winlett ' s face is covered with green hives . A message is sent to London informing them of the situation , but with the bad weather , it will take a few days for a medical team to reach the base . Meanwhile , the Doctor and Sarah Jane Smith arrive at the base by helicopter and are met by Moberley . He tells them that usually up to a dozen live at the base but currently the others are 60 miles away at South Bend , measuring the ice cap . In the sickbay , Winlett ' s body temperature is dropping rapidly , as is his pulse rate . His face and body are now covered with a green fungus , and its growth is accelerating . By the time the medical team arrives it may be too late . However , Mike Wilson from South Bend radios them that the medical team has turned back due to whiteout conditions . The Doctor asks for a blood test on Winlett and examines the now - empty pod . Stevenson acknowledges that it may be his fault ; convinced that the pod was alive , he placed it under a lamp . The Doctor tells him that his actions could result in the destruction of all life on the planet . Moberley draws a sample of blood from Winlett , who is growing increasingly monstrous . Outside the base , the Doctor digs at the ice , uncovering another pod . Stevenson asks if there are any more and the Doctor shakes his head : the pods travel in pairs , " like policemen " . He transfers the pod to the base freezer . On analysis , Winlett ' s blood is found to contain no blood platelets , but instead has schizophytes — microscopic organisms akin to plant bacteria . The sound of engines is heard , and Moberley and Stevenson go meet what they presume is the medical team . The Doctor tells Sarah that Winlett is turning into a Krynoid , a kind of galactic weed that settles on planets and eats the animal life . He does not know exactly how the Krynoids travel between the stars — their planet may be geologically turbulent , with surface explosions sending matter shooting into space . Stevenson and Moberley escort two men — Scorby and Keeler — into the base . The new arrivals were flying a private plane , but they claim they got lost and wound up at the base . The Doctor leaves to check on Winlett , taking the others and leaving Scorby and Keeler alone . Winlett ' s transformation is nearly complete . The Doctor suggests that the arm be amputated to try to stop the spread of the infection at its source . Even if it does not work , it might buy them time . As the Doctor is not a doctor of medicine and Stevenson is a botanist , Moberley is the most qualified . Moberley is hesitant , but Sarah persuades him in the end . As they leave to gather the necessary equipment , Winlett rises from the bed . When Moberley starts back towards the sickbay , he spots Winlett leaning against the wall . As Moberley approaches , Winlett reaches out and strangles him . . . Part two . Winlett leaves Moberley ' s dead body in the corridor and leaves the base . Meanwhile , Scorby finds the base ' s rifle and unloads it . Keeler is nervous , thinking that all they are here to do is to confirm the existence of the pod and report back to Chase , but Scorby disabuses him of the notion : they are to kill the witnessess , take the pod and fly back . Keeler is reluctant , but Scorby warns him that if he refuses , Keeler will be killed . Sarah finds Moberley ' s body . Stevenson cannot believe that Winlett has done this , but the Doctor tells him that Winlett no longer exists ; his mind has been taken over and soon he will turn completely into a Krynoid . They gather their things to search for the creature and take the rifle , not realising it has been sabotaged . When the others leave , Scorby and Keeler go in search of the pod . Dunbar tells Chase about a report of an infection at the base , but he is shocked when Chase tells him he has sent his own men to Antarctica . Dunbar seeks an assurance that should anything go wrong , Chase will protect his identity . Chase pays Dunbar off . The Krynoid finds the generator hut — built far from the base because of its new fuel cell system . However , when it sees the Doctor , Stevenson and Sarah approach , it turns away . Unable to find the Krynoid , and hoping that it is frozen in the snow , the three head back to base , and the Krynoid seeks shelter in the hut after their departure . Meanwhile , Scorby and Keeler ransack the base . When South Bend calls to say the weather has cleared and the medical team are now on their way , Scorby pretends to be Moberley and tells them help is no longer needed . When South Bend gets suspicious , Scorby disconnects the radio . Keeler finds the open pod and realises that it has germinated . Scorby wants to find the actual plant that emerged , but they find Moberley ' s body in the sickbay instead . When Sarah and the Doctor enter the sickbay , Scorby and Keeler hold them at gunpoint . Scorby questions the Doctor about Moberley , and the Doctor tells them about the pod and Winlett ' s infection . When Stevenson discovers them , he finds his rifle useless and is put with the others , but he lets slip that a second pod exists . Scorby wants the second pod . He threatens Sarah ' s life and the Doctor relents , telling Scorby the second pod is in the freezer . Stevenson is forced to take it out and places it in a thermal container to keep it cool and safe . After this is done , Scorby forces Sarah to take him to the generator hut with Keeler in tow , leaving the others tied up behind . While the Doctor knocks over an unlighted kerosene lamp and uses the broken glass to cut Stevenson ' s bonds , Scorby plants a bomb in the hut which will blow up the base . Keeler at first tries to stop Scorby but with no success , and both flee the hut . Freed , the Doctor tells Stevenson to contact South Bend for the medical team and goes in search of Sarah . However , the Krynoid has returned to the base and kills Stevenson while he is making the call . The Doctor sees Scorby and Keeler ' s plane take off and runs to the generator hut where Sarah is tied up . She tells him about the bomb , but the creature arrives as well . They get out the door and lock the Krynoid in ; they run away as the hut explodes , taking the rest of the base with it . . . Part three . Regaining consciousness in the snow , the Doctor and Sarah are picked up by a team from South Bend in their Snow Cat vehicle . Meanwhile , Scorby and Keeler return to Chase with the second pod . Dunbar also arrives , angered at how far Chase had gone to secure the pod . He warns Chase that the Doctor and Sarah are still alive and are scheduled to meet with him and Sir Colin in two hours . At the meeting , the Doctor and Sarah describe how well - planned the theft of the pod was . The Doctor believes that the two men were stooges . The discovery of the pod had only been reported to the Ecology Bureau , so the leak must have come from them . The Doctor is sure that the pod is in England and says that if they do not find it , it will be the end of everything — even Sir Colin ' s pension . He tells Dunbar to arrange for him to go to the Botanic Institute . As they leave the building , a car pulls up , and the driver claims it is theirs . The Doctor and Sarah board the limousine . The car stops in a deserted quarry , and the driver orders them out at gunpoint . As they exit , the Doctor knocks the driver over , and both he and Sarah run for it . With a bit of teamwork , the Doctor jumps the driver and punches him out . The two search the car and find in the boot a painting by Amelia Ducat , who Sarah recalls is one of the world ' s leading flower artists . When they go and speak to her , she tells them that the owner of the painting is Harrison Chase , and she recalls that he never paid her for the painting . Keeler , who is a botanist himself , unsuccessfully tries to convince Chase to stop the experiments on the pod . Chase orders him to inject the pod with fixed nitrogen . Dunbar calls Chase and tells him that his chauffeur is in hospital . When the Doctor and Sarah try to sneak into the mansion , they are spotted by some guards and Scorby , who capture them . The Doctor and Sarah are brought before Chase and , despite having Scorby ' s gun at his head , the Doctor asks Chase grimly to hand over the pod . Chase politely refuses : he has the greatest collection of plants in the world , and when the pod flowers , it will be his crowning achievement . Chase decides to show the Doctor and Sarah around the mansion and his plant laboratory before he executes them . Keeler notes that the pod is growing and tells Hargreaves , the butler , to summon Chase to the annex . There , Chase tells Keeler to inject more nitrogen into the pod . Scorby escorts the Doctor and Sarah into the gardens to kill them , but the two overpower Scorby . The Doctor uses rope to lower Sarah down the wall so she can go and warn Sir Colin , while he returns to the house to examine the pod . However , Sarah gets captured again . The Doctor makes his way back into the mansion while Sarah is escorted by Scorby back to Chase . The Doctor watches , horrified , through the skylight as Chase orders Sarah forced down to a chair , grabbing her arm and pinning it next to the pod . He wants to know what happens when the Krynoid touches human flesh . As Sarah struggles , the pod begins to open . . . Part four . The Doctor crashes through the skylight , knocking Scorby out and grabbing Sarah . They rush out the door , locking Chase and his men in . As Chase tries to get the guards ' attention , a frond from the pod stings Keeler ' s arm . Finally , a guard opens the door ; he and Scorby go in pursuit of the Doctor . Sneaking around the grounds again , the Doctor tells Sarah once more he is returning to examine the pod . Keeler begs Chase to get him to a hospital , but Chase is more fascinated with the transformation process than saving Keeler ' s life . Chase and Hargreaves take Keeler to the nearby cottage . Chase observes that the growth seems to be absorbing protein from Keeler ' s body and tells Hargreaves to keep Keeler fed . When the Doctor returns to the laboratory he finds it empty , but Scorby now has the drop on him . Scorby and the guard take the Doctor to the compost room . Scorby activates the crusher , remarking that Chase recycles everything . The main gate calls the house : Amelia Ducat is here demanding her money . To avoid a fuss , Chase agrees to see her . Sarah has entered the cottage and sees Keeler , who is still lucid , although covered with the Krynoid growth . Keeler tries to convince Sarah to free his bonds , but Sarah , fearing Keeler could transform at any moment , refuses , making Keeler grow more angry and paranoid . Sarah hides in a cupboard when she hears Hargreaves approach with a meal and leaves at the first opportunity . In the library , Chase writes Ducat a check . Scorby enters and asks if they should start the " recycling experiment " , and Chase says he wants to see it , asking Scorby to escort Ducat out . Chase goes to the compost room and reveals that he has been feeding Keeler . The Doctor , tied up , is placed in the machine , to be shredded and pumped into the garden . Sarah is back in the house and hides behind a suit of armour as Ducat and Scorby pass . Sarah attracts Ducat ' s attention and asks her to take a message to Sir Colin . Sarah goes back into hiding when Scorby returns to show Ducat out . Outside , Ducat enters a car with Sir Colin and Dunbar inside and tells them what Sarah said . Dunbar , realising he has made a terrible mistake , says he will go in and get the Doctor . He tells Sir Colin that , if he does not return in half an hour , he must return to London and call UNIT . Sarah finds her way into the compost room and turns off the crusher just in time to save the Doctor . Hargreaves finds that Keeler has now almost completed his transformation and runs in a panic as the creature frees itself . In the mansion , Dunbar pleads with Chase to abandon the experiment as Hargreaves reports Keeler ' s transformation to Chase . Dunbar says that this has gone far enough , and he is going to get help . Chase tells Scorby to stop him . Scorby pursues Dunbar through the grounds as the Doctor and Sarah find Keeler missing from the cottage . The Doctor takes a sword from over the fireplace , and they leave to search for it . Dunbar runs into the Krynoid , which is far larger than the Winlett creature was , and no longer even humanoid . He shoots at it uselessly and is held fast by the surrounding plant life as the Krynoid kills him . Dunbar ' s screams attract the attention of Scorby and the guards as well as the Doctor and Sarah . The latter get there first , the Doctor drawing the sword above Dunbar ' s body as the Krynoid lurches towards them . . . Part five . The Doctor and Sarah Jane arrive just as the Krynoid finishes off Dunbar . The creature advances on them , but Scorby and his men show up and distract it with otherwise useless gunfire . They all escape to a cottage and barricade themselves in . Scorby is shocked that the creature was once Keeler . Chase calls them and orders Scorby to capture rather than kill the Krynoid and cuts off before the Doctor can explain . The Krynoid smashes a window and extends a tentacle inside , but they drive it off . The Krynoid speaks using Keeler ' s voice , demanding that the Doctor come out and join it and it will spare the others . Scorby is more than willing to give up the Doctor until Sarah Jane points out that without the Doctor they have no chance . The Doctor suggests Scorby rig up a bomb so they can all escape while the Krynoid is distracted . Sir Colin tries to get through on the phone while Amelia gives him some advice . Sir Colin tries to contact the Brigadier and UNIT but Lethbridge - Stewart is out of the country . He eventually gets through to Major Beresford for assistance and sends Amelia home . Chase prepares to take photographs of the Krynoid , claiming he has nothing to fear from it . The Doctor and Scorby initiate their plan as Chase arrives outside . Scorby throws his improvised bomb out an upstairs window , and the Doctor makes a run for it . The Krynoid goes in pursuit , but the Doctor escapes in the limousine , leaving the Krynoid behind . Scorby tries to find Chase at the greenhouse and discovers where he is from Hargreaves . They begin barricading the windows in preparation for the Krynoid ' s attack . Chase makes his way through the grounds and confronts the Krynoid . It notices him , and he approaches , taking photographs . It moves toward him as Chase claims he doesn ' t mean it harm . The Doctor arrives at the Bureau as Major Beresford warns he can ' t do anything without evidence . The Doctor warns the Krynoid can channel its power through other plants , turning vegetation against humans . He shows them a series of reports of deaths of people near Chase ' s estates being killed by plants . He then calls Sarah Jane and tells them Beresford is preparing to attack the Krynoid with a laser gun , but the Krynoid cuts the phone wires . Chase wakes up in the woods and has clearly had a major experience : he begins talking about how the world will be recreated . Scorby arrives , and Sarah Jane points out how the vegetation around the windows is getting thicker . When Hargreaves reports that he heard screams , Sarah Jane taunts Scorby into going to investigate with her , and they find a dead guard killed by plants . Chase arrives and tells them that it ' s the plants ' world , and humans are only parasites . He goes to the manor to develop his photographs , then begins speaking to the plants in his greenhouse . Scorby , Sarah Jane , and Hargreaves go in to confront Chase , and he speaks of how the world will be made perfect . They can ' t get through to him as he talks about how he is one with the plants and animals are the enemy . Sarah Jane notices that the plants are closing in on them . The Doctor and a UNIT soldier drive onto the grounds while the plants overwhelm Sarah Jane and the others and start to strangle them . The Doctor and the UNIT soldier , Sgt . Henderson , arrive and bring chemical plant - killer . They dispose of the plants , saving Scorby and Sarah Jane while the butler Hargreaves is dead . Chase runs away , and the Doctor and the others make their way into the lab and start removing the plants . But once they ' re outside , Chase locks the door behind them , and they can only gaze in horror as the now enormous Krynoid towers over them . . . Part six . UNIT soldiers arrive and open fire with their laser gun , distracting the Krynoid so that the Doctor and his group can get to another door . The Doctor believes that Chase is possessed by the Krynoid and determines to find him and eliminate the threat he poses to them from within . After they leave , Chase slips back into the laboratory and destroys the loudspeaker system . Unable to find the millionaire , the others return to the laboratory , and the Krynoid tries to break its way in . Henderson goes to get more timber to barricade the windows , and Chase knocks him out . Scorby starts to panic and wants to run , but the Doctor warns him that every plant on the grounds is under the Krynoid ' s control . Meanwhile , Chase puts Henderson in the compost machine and activates it , killing the unconscious soldier . The Doctor works to repair the loudspeaker system as the Krynoid renews its attack , and Scorby panics and runs for it . He tries to make his way across the grounds through fields of hostile plants and makes his way across a shallow pond , but the plants grab and pull him underwater , killing him . The Doctor and Sarah Jane realise that Henderson is gone , and Sarah Jane goes to look for the soldier . She makes her way to the compost machine room , and Chase confronts her , telling him he ' s become part of the plant world thanks to the Krynoid . Chase plans to support the Krynoid and refers to humanity as parasites , then attacks Sarah Jane . Beresford contacts the Doctor , who warns they have 15 minutes until the Krynoid germinates , spreading its seeds across England . The Doctor tells them to launch an air strike before it ' s too late , and regardless of the fact he and Sarah Jane are at ground zero . Chase has tied up the unconscious Sarah Jane and starts feeding her into the compost machine . The Doctor arrives , sends Chase flying , and shuts off the machine to untie Sarah Jane . He gets her out , but Chase turns the machine back on and throws himself at the Doctor , and the two struggle inside the machine ' s bin . The Doctor climbs out as Chase is pulled into the machine , despite the Doctor ' s efforts to save him . The RAF launches a sighting run as Beresford and Sir Colin look for any signs of the Doctor . Sarah Jane and the Doctor can ' t get out through the plant life covering the house , but the Doctor rigs a steam pipe , and they blast their way out . They make their way through the hostile plant life and take refuge in a clearing filled with cut - down trees , as the RAF opens fire and destroys the Krynoid . Later , the Doctor , Sarah Jane , and Sir Colin discuss the apparent destruction of the Krynoid . Sir Colin wants the Doctor to address the Royal Horticultural Society , but the Doctor instead offers to take Sarah Jane on a vacation to Cassiopeia . However , the TARDIS materialises in Antarctica when the Doctor forgets to reset the coordinates . Simultaneously , the Doctor and Sarah Jane say , " Have we been here before or are we yet to come ? " Home video and audio releases . Video releases . This story was released in the UK on VHS video in 1994 , Australia later in 1994 and the US in 1995 . DVD releases . This story was released on DVD 25th October 2010 . The two disc release contains the following extras : CD release . In 2000 a CD was released with " Terror of the Zygons " .