“Milo” (Michael Caine) arrives at the stately pile of a renowned crime writer - a sort of male Agatha Christie, and has to navigate a complex maze to track down his voice. The dapper “Andrew” (Sir Laurence Olivier) welcomes his guest effusively and takes him into his home. It’s an Aladdin’s cave of theatrical props and costumes which leaves “Milo” a little unnerved. Not as unnerved as he’s going to get, though, when “Andrew” declares his knowledge of the affair his wife is having with him and that he’s relatively relaxed about her leaving so long as he can get the insurance on £175,000 worth of...