From the Radio Times:

5.50 Colour
Dr Who
starring Jon Pertwee
The Sea Devils
by MALCOLM HULKE
Part 4
Sea Devils attack the patrolling submarine.  The Doctor persuades Captain Hart to investigate the prison, but arrives too late.




Title music by RON GRAINER and the
BBC RADIOPHONIC WORKSHOP
Incidental music by MALCOLM CLARKE
Script editor TERRANCE DICKS
Designer TONY SNOADEN
Producer BARRY LETTS
Director MICHAEL BRIANT

From the Radio Times  (This is for the omnibus edition that repeated the show in a condensed version without episode breaks):

3.5 Colour
Dr Who and the
Sea Devils
The complete adventure
in one programme starring
Jon Pertwee as Dr Who
Written by MALCOLM HULKE
Now you can see again the whole of the Doctor's struggle against the Master and the strange creatures from the bottom of the sea.
Title music by RON GRAINER
and the BBC RADIOPHONIC WORKSHOP
Incidental music by MALCOLM CLARKE
Script editor TERRANCE DICKS
Designer TONY SNOADEN
Producer BARRY LETTS
Director MICHAEL BRIANT
(In next week's RADIO TIMES there's a cover feature on all three Dr Whos and their assistants)