AllMovie

In the fifth episode of the six-part story "The Sea Devils," the Doctor (Jon Pertwee) realizes he will never be able to negotiate a truce between the British Navy and the reptilian Sea Devils as long as the Master (Roger Delgado) is stirring up hostilities. Things become even hairier when the Master develops a machine that will enable the Sea Devils to win their battle at sea and to wipe out all mankind. With no other alternative, the Doctor and the Master square off in a fight to the finish. Originally shown on March 25, 1972, "The Sea Devils, Episode 4" was written by Malcolm Hulke.