Debut screen appearance by Teris Hebrew. This is, in fact, the director of the episode, Herbert Wise, making an extremely rare acting appearance. (The two names are anagrams).
Photo 4 is not from this episode. It is from s2 e11 'The Umbrella Man'.
This is the first of three episodes that Lucy Gutteridge has appeared in, the other two being S6 E9, The Wrong 'Un (1983) and S9 E8, The Finger of Suspicion (1988).
Directed by Herbert Wise who had previously directed Derek Jacobi in I, Claudius (1976), which more or less made Derek a star.