It's interesting to see Sid James play a straight (albeit brief) role for change in this simple little crime thriller. He is a wealthy chap with a rather venal second wife and step-daughter. His obsession with mysticism leads, one evening, to a risky experiment and it all goes wrong... We have no absence of potential culprits as his new family try to drive his daughter out of her mind so they can inherit his fortune. Betty Ann Davies is good as the scheming the wife, with Sheila Burrell likewise as her ghastly, grasping, daughter all manipulating poor old "Joan" (Hazel Penwarden) in a decently paced mystery. Sadly the ending is writ a bit large from fairly early on, and that makes it all sag a bit - maybe Francis Searle could have tightened it up by a quarter of an hour? It's still an enjoyable watch, though - with a slightly more sophisticated script (that may owe something to it's BBC radio heritage). It is rarely shown nowadays, but is worth seeing through if you encounter it.