Hywel Bennett is the actor, he plays Martin Durnley in a controversial 1968 BAFTA award winning British film, That also stars Hayley Mills as Susan Harper, and Billie Whitelaw as Joan Harper who incidentally was the person that won the 1969 Best Supporting Actress Award at the BAFTAS for her part in this film. It is of course Twisted Nerve.

Dx, Severely Emotionally Disturbed, Patricidal, Serial killing Psychopath, That is my own interpretation after watching the film earlier this week on cable.

Here is a link pertaining to the film.

http://en.wikipedia.org/wiki/Twisted_Nerve