I see ld has been reading Dingwall

Following on from the mentions of mirrors previously: Sirhan claimed "my mirror" told him to do it. His alter, perhaps. That was mentioned in RFK must die, which also has a repeated shot of some bloke with one half of his face in darkness. Sometimes his face is shown on each side of the screen, bothly with the out-facing side lit. In The Three Hostages the character Dominic Medina uses his own half-lit face to hypnotise people in a darkened room. The author of that, of course, was Buchan, the Scots aristocrat and spy/propgandist.