The Sirens of Time ( audio story ) The Sirens of Time was the first in the series of " Doctor Who " audio dramas produced by Big Finish Productions . Written and directed by Nicholas Briggs , the four - part story featured the Fifth , Sixth and Seventh Doctor s , with Peter Davison , Colin Baker and Sylvester McCoy each reprising their roles from the original television series . Publisher ' s summary . Gallifrey is in crisis , facing destruction at the hands of an overwhelming enemy . And the Doctor is involved in three different incarnations — each caught up in a deadly adventure , scattered across time and space . The web of time is threatened — and someone wants the Doctor dead . The three incarnations of the Doctor must join to set time back on the right track — but in doing so , will they unleash a still greater threat ? Plot . Part 1 . A TARDIS arrives on Gallifrey , flown by Coordinator Vansell . He is confronted by security forces , but claims the planet is in terrible danger and demands to see the Lord President , who learns that he is right . Their planet is under siege by an unknown species . Vansell also informs the Lord President that traces of artron energy have been detected in some form of time distortion — that of the Doctor . In the Seventh Doctor ' s TARDIS , things seem to be running normally when suddenly the Cloister Bell goes off . A strange , almost hypnotic sound is heard and the Doctor alters the ship ' s co - ordinates , immediately wondering why he has done so as the ship lands . A Time Lord tries to communicate with the Doctor , but the signal is cut off before he can reveal his message . The Doctor hears the sound again , coming from outside the TARDIS . Leaving the TARDIS , the Doctor hears a distant voice calling for help . A girl called Elenya is trapped in quicksand . He tells her not to struggle as he hacks his way through the undergrowth with his umbrella . A mysterious woman appears and laughs at the Doctor . He ignores her and goes to the aid of Elenya . Using his umbrella , he pulls her out of the bog and onto a safe patch of land . Sancroff , who is a prisoner in the home of the woman , Ruthley , is waiting for her return . She tells him that she hates her job , which is to tend to him and prevent him from leaving . Ruthley reluctantly helps Sancroff into his bed . Speaking through a communicator with guards hovering above the planet , she then lies and tells the guards that there are no visitors on the surface . Meanwhile , The Doctor finds himself locked out of his TARDIS . Elenya explains about her arrival ; she is a geologist and her friends , her tutor and her pilot have been killed in a crash on the planet . A ship suddenly breaks through the planet ' s atmosphere and crashes into the surface . The Doctor and Elenya walk across the surface to try to find some kind of civilisation . The Doctor spots light from a window , and the two begin to head towards it . More ships come bursting through the planet ' s atmosphere , including one which crashes very close to where they are walking . Back at Ruthley ' s house , she communicates with another life form through her communicator , who confirm that they are deploying themselves to the planet ' s surface . More ships are crashing down all around the Doctor and Elenya . They investigate one ship ' s fiery wreckage and find what they initially believe are the remains of the crew . The Doctor deciphers that the creatures are actually in the process of being born . Meanwhile , a security Drudger reports back to Ruthley that they have extinguished the fires from one crashed ship and located two survivors ( the Doctor and Elenya ) . She asks them to kill the two , but the Drudger responds that such a procedure is " not permitted " . The Doctor and Elenya meet up with several Drudgers , who ask them to surrender any weaponry and identify themselves . They then begin a mind scan of the two , which is extremely painful and knocks the Doctor and Elenya out cold . When they awake , they are at Ruthley ' s house and Sancroff is with them . The Drudgers encounter bio - engineered life forms ( the assassins ) emerging from the wreckage that the Doctor and Elenya encountered earlier . A Drudger confronts the assassins , who open fire and destroy it . Ruthley gloats to Sancroff that the assassins are here to kill him , as they destroy more Drudgers . Sancroff realises that Ruthley has done a deal with the assassins ; he tells the Doctor and Elenya to leave , but the Doctor responds that there is no way for them to leave the planet . The Drudgers return fire , but nothing seems to be working ; they retreat . The assassins are converging on the main building . The Doctor , Elenya and Sancroff enter Ruthley ' s room , as she goes to tell the assassins where they are ; they find live footage of Ruthley speaking to the assassins . They kill her because she would be a " witness " . The others learn that Sancroff is ( or was ) First Knight of Velyshaa ; the Doctor tries to create a forcefield , but the creatures find them before he has the chance . One of the assassins plays a message which brands Sancroff a war criminal , and sentences him to execution . The Doctor informs the assassins that he and Elenya are there by accident ; they respond that they have no quarrel with either of them , but that there must be no witnesses , and open fire . . . Part 2 . Inside a German U - Boat , Captain Walther Schwieger and his second in command can see a merchant ship approaching . They decide whether or not to send a torpedo at it . On the merchant ship , the TARDIS arrives and the Fifth Doctor emerges . He ' s searching for a signal of some kind . It finally locks on and the Time Lords try to contact him . The message is unclear , but they apparently want him to re - enter the TARDIS because time is running out . The Doctor tries the lock , but the ship won ' t open , he calls for Turlough and Tegan Jovanka , but they don ' t open the door . A woman by the name of Helen appears . She asks what he is doing on board the ship . Suddenly , there ' s a large explosion as a gun from the U - Boat hits the side . Aboard the U - Boat , the Captain sees two survivors , they bring them board . The Captain is surprised that the Doctor can speak German . They are both placed inside a cell . Helen is worried whether the Doctor is maybe a Hun spy . The Doctor is even more worried about his message from the Time Lords . He tries calling to the Germans to free him . British destroyers are gathering on the surface and so the German Captain decides it is time to escape the area . The Doctor wishes to speak with him . He tries to persuade him that he is actually a German spy and has found secret documents aboard the ship , which is now reduced to wreckage . The Captain does not believe him . He orders Schmidt to return him to his cell . Back in the cell , Helen watches as Schimdt suddenly become possessed by some force and tries to kill the Doctor , who deduce s that it is the Time Lords who are trying to kill him for some strange reason . The Captain arrives and orders Schimdt to be tied to his bunk . The Time Lord President is unsure of Vansell ' s actions to try and stop the Doctor . Using someone by time distortion wasn ' t the best idea . Vansell disagrees and counters that the Doctor must be stopped for the sake of time . The German commandant can see smoke on the horizon , claiming it is British ships approaching . In his cell , the Doctor is wondering why the Time Lords want to kill him . He tells Helen that he needs to return to his TARDIS . Helen can sense that it ' s important to him somehow . Schmidt is now awake and can hear voices in his head . It is the voice of Vansell and he is telling him to grab a weapon and to kill the Doctor . The Germans discover that the ship is large and is coming towards them at a speed that they wouldn ' t be able to match , let alone outrun . Schmidt has now entered the cell with a gun pointed at the Doctor . The Doctor tries to reassure him that they do not know each other and reasons why he shouldn ' t kill him . The Lord President is still trying to stop Vansell , realising that the Doctor knows what he must do . There ' s a shot , which the Germans in the control room can hear . The Captain goes to see what has happened . Helen has managed to take the gun , but Schmidt collapses , a side effect of the time distortion . The Captain and crew arrive , but Helen has them at gunpoint . The Doctor is hoping to discover his ship again . The Doctor navigates the U - Boat to the position of the TARDIS . He escapes the ship and jumps into the water . The British ships are closing and the U - Boat goes back under . The Doctor reaches his ship , but has no luck in opening the doors . He is trapped , floating at sea . " more to be added " Part 3 . " to be added " Part 4 . " to be added "