The Doctor and Jo visit the Master in his island prison. Besides visiting his old friend the Doctor is after assurance that the Master is secure - that he hasn't managed to use his hypnotism to escape. Colonel Trenchard gives the Doctor the impression that the guards are impervious to hypnotism.
Colonel Trenchard lets slip that ships have been disappearing, and the Doctor decides to have a look. After triangulating three of the disappearances the Doctor finds an abandoned base, and starts his investigations there - and Jo tags along. Whilst there they are attacked by Sea Devils, related to the Silurians.
The Doctor manages to escape and notifies the Navy, who want to launch an attack. The Master is involved, with Colonel Trenchard assisting. The Doctor stalls the Navy by offering to negotiate, but with the Master present this is difficult. The Doctor pretends to help the Master construct a machine that will enable the Sea Devils to emerge victorious, but instead sabotages it, and the Doctor and the Master escape as the Sea Devils' base is destroyed.
The Master fakes illness. He hypnotises, and disguises, one of the rescue crew, and manages to escape from the authorities.
Regular castJo Grant: Katy Manning;
Guest castThe Master: Roger Delgado; Captain John Hart: Edwin Richfield; Third Officer Jane Blythe: Jane Murphy; Colonel George Trenchard: Clive Morton (1-4); Sea Devil: Pat Gorman (1-2,4-6); LDG Telegraphist Bowman: Alec Wallis (1,4-6); Castle Guard Barclay: Terry Walsh (1-3 - uncredited for 2); Alan Clark: Declan Mulholland (1-2); Radio Operator: Neil Seiler (1); Edwin Hickman: Hugh Futcher (1); Robbins: Royston Tickner (1); Castle Guard Wilson: Brian Justice (1); CPO Smedley: Eric Mason (2); Lieutenant Commander Tony Mitchell: David Griffin (3-5); Commander Ridgeway: Donald Sumpter (3-5); LDG Seaman Lovell: Christopher Wray (3-5); Castle Guard Drew: Stanley McGeagh (2-4); CPO Summers: Colin Bell (4-5); Lieutenant Commander Watts: Brian Vaughn (4); Chief Sea Devil: Peter Forbes-Robertson (5-6); Walker: Martin Boddey (5-6); A/B Girton: Rex Rowland (5); Rear Admiral: Norman Atkyns (5); CPO Myers: John Caeser (6);
Uncredited cast: Voice of DJ: Michael Briant (2); Sea Devils: Steven Ismay, Brian Nolan, Frank Seton, Jeff Witherick; Chateau Guards: Stewart Barry, Bob Blaine, Les Clark, Jim Dowdall, Brian Gilmar, Phillip Weston; Ratings: Jim Dowdall, Nick Llewellyn, Roy Pearce, Dennis Plenty, Ron Tingley; Naval Base Sailors: Jim Dowdall, Brian Gilmar, Nick Llewellyn, Roy Pearce, Dennis Plenty, Ron Tingley, Phillip Weston; Stuntmen: Marc Boyle, Peter Brace, Alan Chuntz, Jack Cooper, Stuart Fell, Billy Horrigan, Mike Horsborough, Mike Stephens, Terry Walsh, Derek Ware;
|BBC 1||312||Episode One||Sat 26 February 1972||5:50 pm - 6:15 pm||6.4M||76th|
|BBC 1||313||Episode Two||Sat 4 March 1972||5:50 pm - 6:15 pm||9.7M||26th|
|BBC 1||314||Episode Three||Sat 11 March 1972||5:50 pm - 6:15 pm||8.3M||45th|
|BBC 1||315||Episode Four||Sat 18 March 1972||5:50 pm - 6:15 pm||7.8M||40th|
|BBC 1||316||Episode Five||Sun 26 March 1972||5:45 pm - 6:10 pm||8.3M||39th|
|BBC 1||317||Episode Six||Sat 1 April 1972||5:50 pm - 6:15 pm||8.5M||47th|
Repeats (on the BBC)
HMS Reclaim; Norris Castle, Cowes, Isle of Wight; No Man's Land Sea Fort, Solent;
Television Centre Studio 8;
Bloopers and mistakes
The radio that the Doctor built couldn't have worked. If you look at the device (this is clearest right before it explodes), you can see that there's a 9 volt battery clip sticking out of it. The blooper is that there is no battery in the socket, so electricity cannot flow between the two metal terminals. Therefore the whole thing shouldn't be able to work at all because there isn't a complete circuit.
Episode 1: The Doctor has a telescope, which he uses to look at the Master's prison with. Yet when the camera switches to the close up of the castle, it shows the view from a pair of binoculars.
Episode 1: When Jo and the Doctor are climbing the ladder to get into the sea-fort it's painfully obvious that it isn't Katy Manning, but a bloke in a Jo Grant wig.
Episode 2: When the Doctor and Jo are carrying the fat guy out, you can see shadows and light moving around in the background as if there's someone there.
Episode 3: When the submarine crashes to the sea bed there is a shot of the sub falling, cut to the inside and the crew fall around a bit. Then the sub hits the sea bed, in a model shot, then cut back again and they fall around a bit more.
Notes and trivia
This was the last story that the Havoc team as a whole worked on.
Episodes One to Three exist in a converted NTSC format suitable for UK transmission.
This programme has no other working titles, or they have not been yet been entered.