Frontier in Space ( TV story ) Frontier in Space was the third story in season ten of " Doctor Who " . It saw the introduction of the Draconian s and the reappearance of . It was loosely connected with the following serial , " Planet of the Daleks " , and is significant for showing an alliance between the Master and the Dalek s . It is further notable as the final appearance of Roger Delgado in " Doctor Who " before his death . In June 1973 , Delgado died in a car accident in Turkey when the chauffeur - driven vehicle ran off the road and fell into a ravine , during the on - location shoot for the film " Bell of Tibet " . His character was meant to have a final encounter with the Doctor in the serial " The Final Game " , which was scrapped . " Frontier in Space " was the Master ' s last appearance until Robert Holmes and Philip Hinchcliffe brought the Master back as the main villain of " The Deadly Assassin " , albeit in a decaying form played by Peter Pratt . The story also saw the first use of a refitted version of the sonic screwdriver model which debuted in " Colony in Space " . Instead of a silver emitter ring head , it now sported a red emitter ring head , with the addition of two semi - circular black magnets attached to the end , and the extending section of the screwdriver which once contained a red band and a set of alternating yellow and black coiling stripes was now unpainted in a plainly metallic colour scheme . This model of the sonic screwdriver remained in use by the Doctor all the way up to his fifth incarnation midway through season 19 , where it was written out of the series in " The Visitation " . Synopsis . The Third Doctor and Jo are caught in the escalating tension between planets Earth and Draconia and discover that is secretly working to provoke the two into all - out war . Plot . Episode one . As the Earth cargo ship C982 moves through hyperspace , it narrowly avoids a collision with the TARDIS , which dematerialises out of the way and rematerialises in the ship ' s hold . The Third Doctor determines that they are in the 26th century . Jo sees a ship come alongside and hears a strange , high - pitched buzz . The ship shimmers , turning into a Draconian Galaxy - class battlecruiser . The two pilots , Stewart and Hardy , send out a distress signal and prepare for battle . When Hardy goes to get weapons , he meets the Doctor , but , thanks to the sound emitted by the enemy ship , he sees the Doctor and Jo as Draconians whilst Jo sees Hardy as a Drashig . Hardy escorts them at gunpoint as the Draconian captain orders C982 to surrender its cargo or be destroyed . On Earth , the President and the Draconian ambassador ( who is also the Emperor ' s son ) accuse each other of attacking their ships and violating the frontier between the two empires established by treaty . General Williams reports to the President that a mission to rescue C982 is being prepared . Williams ' s hostility to the Draconians is well known — it was his actions that started the last war between the two — and the Prince believes Williams wants war again , a war , the Prince warns the President , that will see Earth destroyed . News of the attack spreads and anti - Draconian riots break out on Earth . The opposition calls for the government to take action . Locked up in C982 ' s hold , the Doctor deduce s that the strange sound was some kind of sonic hypnosis device that caused Hardy and Jo to see what they most feared . As the boarding party burns through the airlocks , Hardy gets the Doctor and Jo to use as hostages , but when the airlock door bursts open , the boarders are not Draconians , but Ogron s . The Ogrons stun the two pilots and the Doctor . They tie up Jo and take the ship ' s cargo and the TARDIS as they leave . When the Doctor revives and releases Jo , she tells him what the Ogrons did and wonders if they are working for the Dalek s , as they were when she first met them . The Doctor points out that the Ogrons are mercenaries . When the rescue party arrives , Hardy and Stewart have stopped hallucinating , but with their memories garbled , they accuse the Doctor and Jo of being Draconian traitors . . . Episode two . The two travellers get locked up again as C982 heads back to Earth . General Williams believes the Doctor and Jo are human agents planted by the Draconians to sabotage any war effort by Earth . He brings the two travellers to confront the Draconian Prince , but the Doctor denies working for the Draconians . He tries to convince the President that a third party is trying to provoke the two empires into war . However , as the Doctor can provide no reason why someone would want to , Williams orders him and Jo be taken away and vows he will get the truth out of them . In the Draconian embassy , the Prince arranges to help Jo and the Doctor " escape " so they can be questioned . When the two are escorted from their cell to be brought to the President , a Draconian squad attacks , taking the Doctor prisoner . Jo tries to get more guards to help , but she is arrested instead . The Draconians question the Doctor , believing that he is involved in a plot with Williams to provoke a new war . The Doctor escapes but is recaptured in the compound by Earth troops . Once he is back in the cell with Jo , she hears the same sound as on C982 . Outside , the Ogrons raid the prison , looking like Draconians thanks to the hypnosound . They break into the Doctor ' s cell and order him to go with them . Episode three . The second escape goes no better than the first : the Doctor is recaptured again , and the Ogrons disappear . This second " rescue attempt " cements Williams ' suspicions . He demands the president grant him the authority to strike first against the Draconians . The president agrees to break off diplomatic relations but will go no further without conclusive proof . Williams puts the Doctor under a mind probe . It indicates the Doctor is telling the truth . Williams refuses to believe it and orders increased power , but the probe overloads . The president orders the Doctor sent to the Lunar Penal Colony , where political prisoners are exiled for life , while Jo remains on Earth . Williams and the president receive records from the Dominion government of Sirius IV , a colony planet that with some autonomy . The records " prove " the Doctor and Jo are citizens of Sirius IV and career criminals . A commissioner from the Dominion has arrived to claim jurisdiction — the Doctor ' s old enemy , the Master . On the Moon , the Doctor meets Professor Dale of the Peace Party , who shows him around . The Doctor tries to gain Dale ' s trust and include him in his plans for escape . On Earth , Jo recognises the Master immediately and realises he was behind the Ogron attacks . The Master discovered the Doctor and Jo ' s presence when the Ogrons brought him the TARDIS . Given the unsavoury choice of going with the Master or staying in her cell , Jo agrees to go with him to fetch the Doctor . Dale believes the Doctor . The peace with the Draconians lasted many years but suddenly devolved into senseless acts of hostility . The Doctor ' s fantastic story explains everything . Dale outlines the escape plan : Cross , one of the overseers , will leave two spacesuits near an airlock . They will cross the lunar surface and steal a spaceship . Dale offers to take the Doctor back to Earth where he can tell his story to Dale ' s contacts in the press and government . However , once inside the airlock , they find that the suits ' oxygen tanks are empty . The Doctor tries to open the door , but it is locked . He and Dale realise Cross has tricked them and is pumping out the room ' s air . . . Episode four . At the last moment , the Master arrives and restores the room ' s atmosphere . He obtains custody of the Doctor and gets the Doctor to come along quietly by revealing that he has Jo . Reunited with Jo in a cell in the Master ' s ship , the Doctor wonders why he is still alive . The Master explains that his employers are very interested in the Doctor . The Master sets the automatic controls for the Ogron homeworld . Pretending to tell Jo stories of his life , the Doctor uses a hidden steel wire to file through the cell ' s hinges . Jo blocks the security camera and natters , pretending to continue the conversation , while the Doctor sneaks out . Donning a spacesuit , he makes his way across the hull and into the flight deck . The Master puts Jo in an airlock , threatening to eject her into space if the Doctor does not surrender . The Doctor takes him by surprise . As the two face off , they do not see a Draconian battlecruiser approaching . Draconians enter the airlock where Jo is located . The Draconian captain tells them all diplomatic relations with Earth have been severed . Violating Draconian space is punishable by death . The Doctor says he has vital evidence for the Emperor and asks to speak to him . The captain locks up all three of them to take back to Draconia . However , the Master secretly activates a device whose signal is picked up by the Ogrons . Episode five . As the ship arrives on Draconia , the prince is speaking with his father , asking for permission to strike first at Earth . The emperor , like the president , is hesitant . He knows such a war could bring down both empires . The Doctor , Jo and the Master are presented to the emperor , and the Doctor gives the ritual greeting , " My life at your command . " The prince is incensed that the Doctor has the temerity to address the emperor like a Draconian noble , but the Doctor says that he " is " a noble of Draconia — the title was given him by the 15th emperor , five centuries before , when he aided Draconia against a space plague . The Doctor accuses the Master of trying to start a war between Earth and Draconia using Ogrons and the hypnosound device . As the emperor considers this , a courtier announces that an Earth spaceship has arrived . Jo hears the sound of the sonic device and realises it is the Ogrons . They burst in , guns blazing , and retreat with the Master , leaving several dead Draconians in their wake . One Ogron has been knocked out by the Doctor . As the effects of the hypnosound fade , the emperor sees the " Earthman " before him transform into its true form . He realises the Doctor is speaking the truth . The emperor decides the Ogron must be shown to the Earth authorities , but a Draconian ship would be shot down . The prince , the Doctor and Jo will take the Master ' s police ship . As they cross the frontier into Earth space , they spot a ship following them . By the time they identify it as the Ogron ship , it has already launched its missiles . As the Doctor takes evasive action , the captive Ogron breaks out of its cell , overpowering its Draconian guard . It enters the flight deck and in the struggle cuts the ship ' s speed . The prince and the Doctor subdue the Ogron , but the Master ' s ship catches up and a party boards the ship . A firefight breaks out on the flight deck , just as an Earth battlecruiser shows up . The Master recalls the boarding party , who rescue the Ogron prisoner and take Jo captive . Their ship zips away . The Earth battlecruiser places the Doctor ' s ship under arrest . Without the Ogron , the president is not convinced . The Doctor suggests a trip to the Ogron homeworld , but Williams thinks it a Draconian trick to divide Earth ' s forces . The prince expects this response from Williams — after all , he started the first war . Williams protests , but the prince reveals what is in the Draconian court records . Twenty years before , the Draconians sent a battlecruiser on a diplomatic mission . When the Draconian ship did not answer hails , Williams gave the order to attack . The battlecruiser was unarmed , its missile banks empty , and the reason it did not answer was because its communications systems were destroyed in the same neutron storm that had damaged Williams ' s ship . Williams is shaken by the prince ' s revelation and apologises for the wrong he had done to the Draconians . Williams now intends to lead the expedition to the Ogron planet himself . The Master brings Jo to a bunker on the Ogron homeworld , where he shows her the TARDIS . He plans to use Jo and it as bait for the Doctor . He tries to hypnotise Jo , first with his own powers and then with the hypnosound . Episode six . Jo ' s mind is strong enough to resist . The Master orders her taken away . An Ogron reports that one of their ships found and attacked two Earth cargo ships , destroying one . The Master is delighted . This means that war is not far off , and , indeed , cries for war from Earth are at a fever pitch . Williams prepares his personal scout ship . The Doctor and the prince accompany him as it heads at top speed to the coordinates the Doctor got from the Master ' s ship . Jo digs her way into the next unlocked cell and sneaks further into the bunker as Williams ' s ship enters orbit , and they avert near destruction from a Draconian cruiser . She pockets the hypnosound , then finds a pad with the coordinates of the planet and bunker . She transmits a distress signal with the information . The Master shows up , revealing that the signal was muted , and only the Doctor could read it . His ship has been detected in orbit . When he comes , the trap will be sprung . Williams ' s party lands nearby , not knowing the Ogrons have set up an ambush . The Ogrons open fire on them but are frightened away by an orange , slug - like lizard they call the Eater . The Master is furious . He warns them their masters are coming . This terrifies them more than the monster . Williams ' s group hears the roar of a landing spaceship . When they look at the ridge , they see the Master , accompanied by several Dalek s , who exterminate Williams ' men before they can fire . The Daleks want to exterminate the Doctor immediately , but the Master proposes that the Doctor be placed in his hands , to be allowed to see the galaxy and Earth in ruins before they kill him . The Gold Dalek agrees and leaves for its ship to prepare the Dalek army on another planet . The Doctor explains the Daleks want a war between Earth and Draconia so both empires will destroy each other and the Daleks can pick up the pieces . The Doctor modifies the stolen hypnosound , making the Ogron guard see him as the Gold Dalek . In fear , it unlocks the cell gate . The Doctor tells Williams and the prince to get the word to their respective governments and mount a joint expedition against the base on the Ogron planet . The Doctor and Jo find their way to the TARDIS but are surrounded by the Ogrons and the Master , who trains a blaster on the Doctor . The Doctor activates the hypnosound , panicking the Ogrons . One knocks the Master ' s arm , making him fire , the shot grazing the Doctor ' s head . The Master and the Ogrons scatter . The Doctor , barely conscious , has Jo help him into the TARDIS . He staggers to the console , dematerialises the ship , then presses his palms to the telepathic circuits , sending a message to the Time Lord s . The TARDIS spins away into space . . . Home video and audio releases . DVD releases . This story was released in a box set called " Dalek War " , along with " Planet of the Daleks " . The DVD was released in the UK ( Region 2 ) on 5 October 2009 , in Australia and New Zealand ( Region 4 ) on 4 February 2010 , and in North America on 2 March 2010 . Digital releases . This story is available :