Aired Feb. 26 - Apr. 1, 1972
Written by Malcolm Hulke
Directed by Michael E. Briant
Traveling to England's southern coast, the Doctor and Jo arrive at the maximum-security island prison housing the Master. There they meet the warden, Colonel Trenchard, who informs them that the Master has been a model prisoner. Meanwhile, he also tells them about the mysterious disappearances of several ships off the coast.
Intrigued, the Doctor heads to a nearby naval base to investigate. The commanding officer, Captain Hart, informs him that the incidents have all occurred near a sea fort scheduled for demolition. The Doctor and Jo travel to the fort, and find that the men there have been attacked by what they call Sea Devils, whom the Doctor deduces are an amphibious offshoot of the Silurians.
While the Doctor again tries to find a peaceful solution, his efforts are thwarted by the Master, who has convinced Trenchard to help him steal equipment from the naval base in an attempt to revive the Sea Devils and foster a conflict.
Once the Sea Devils capture the naval base, the Master has them take the Doctor to their undersea control centre to assist him in reviving the rest of their people. When it becomes clear that, due to misunderstandings and the Master's manipulations, peace will not be possible, the Doctor is forced to modify the machine and rig it to explode. The Time Lords manage to escape just as the machine detonates and the base is destroyed.
The Doctor and the Master are rescued from the sea by the Navy, but in the confusion, the Master escapes to wreak havoc another day.
There's a whopping great problem with The Sea Devils, and it's particularly apparent if you've been watching the series like I have; in order over an accelerated time-span. It's virtually a retread of Doctor Who and the Silurians, except all the complexity and tension of that story has been jettisoned in favour of action set-pieces and the Master. And by retread, I mean, the central conflict and themes are exactly the same.
But, the thing to remember is that, when The Sea Devils was made, people couldn't watch Doctor Who like that. Two years later, how many viewers even remembered the original story all that well? Probably few enough that writer Malcolm Hulke and the production team felt safe in repeating itself. It's not a great move, but it can be forgiven when viewed through a historical perspective.
And, truth be told, while it's definitely less finely made than the original story, The Sea Devils is just as fun, albeit in a completely different way. The simmering, grim tension of the earlier story gives way to a jubilant action spectacular, with jet skis and hovercrafts and sword fights and exploding land mines! The result is one of the most enjoyable Third Doctor-era adventures, featuring the Doctor and the Master's conflict at its height. It may not be bold, but it is enjoyable.
Of course, the plot is recycled, and there's an overall tone that feels a bit too comfortable, a little too close to coasting, but there are some strong moments too. The best example is the relationship between the Master and Trenchard. The Master's typical MO is to simply hypnotize people into allying themselves with him, but here we see the Master using manipulation, playing off of Trenchard's reactionary patriotism, a move that was surely instigated by Hulke. The result is a different relationship to what we've previously seen, and when the misguided Trenchard gives his life to protect the Master, there's genuine pathos and feeling there. It's a small example of what made Hulke unique among Doctor Who writers.