Doctor Who "The Sea Devils - Episode Four" (1972)

As we move into the second half of the serial, the stage is set for the Master's final end game. His callous disregard for Trenchard and his death at the hands of the Sea Devils demonstrates the low regard the Master has for human life. Trenchard was never a despicable character, in fact quite the opposite. It was obvious that he was being played from the beginning as the Master knew which buttons of his to push to get him to go along with his plans. It slowly starts to dawn on him that the Master is being deceptive until this episode where it becomes obvious that the Master is looking to work with the Sea Devils. Trenchard shows true courage in the end standing his ground while his guards flee for safety and his death off-screen leaves the character with a final sympathetic note.

We see more of the Sea Devils here than in previous episodes as they take over the submarine that has been sent to investigate the missing ships and their siege of the prison. Now the costumes for the Sea Devils have mostly been used in scenes taken on location by the film crew. As these scenes are always filmed first, the original Sea Devil heads were rushed for the production. However as the studio scenes for the episodes were shot, the costume designers decided to fine-tune the design, giving them a more aquatic, natural look. Until now where the Sea Devils are seen in great numbers in studio scenes, it hasn't been previously apparent of the design change.

We also get to see more of Captain Hart as the Doctor continues to persuade the naval officer that his claims of the existence of the Sea Devils and their alliance with the Master are true. Richfield plays Hart with a stoicism and noble air as he is gradually won over as an ally of the Doctor. Even towards the end his character shows concern that the Doctor heads down into the Sea Devil base alone with a peace offering. Captain Hart essentially takes the place of the Brigadier in this serial and it's an effective method to show how commanding and persuasive the Doctor can be. Hart goes from thinking the Doctor is quite mad in the first episode to trusting him by the middle of this episode and he and the Doctor don't get much screen time together in the episodes in between.

I also want to make a quick note here about the cooperation the production crew was able to retain from the Royal Navy. The last sequence takes place aboard an actual diving vessel with the crew performing the act of lowering and raising a diving bell. This service, along with the use of a naval base and naval personnel was done free of charge and provides an extra added layer of realism to the proceedings. In the end the Doctor has mysteriously disappeared from the diving bell and Hart and Jo are perplexed and worried regarding his current whereabouts.

Favorite moment: In Captain Hart's office, 3rd Officer Jane Blythe (June Murphy) brings in some sandwiches for Jo. The Doctor promptly snatches the plate away asking if she thinks this is a picnic. The comical scene where the Doctor proceeds to eat the sandwiches, then offer some to Captain Hart and Blythe and leaves Jo with an empty plate is a great absent-minded Doctor moment. Jo's disappointment and the Doctor's dawning realization of what he just did are priceless moments. Scenes like these are the benefit of the serialized storytelling style of the original series. The new series is unable to have many scenes like this outside the two-parters and it's a shame because it's character moments like these that are the most memorable.