Season 1, Episode 4
Poor little Tessa. Is she a sociopathic killer or just a girl framed for a murder she didn't commit? This is the question posed by The Mark of the Hand, capably directed by Paul Henreid [Casablanca, Alfred Hitchcock Presents] from a novel by American mystery writer Charlotte Armstrong. The subject matter is one that has been covered many times before. The best example being The Bad Seed  which is one of my all time favorites in the "disturbing children" category. The problem with this episode is that the "twist" actually robs the film of its power. It's always more interesting to go darker than lighter and The Mark of the Hand misses its chance to shock the audience.
That being said, there is still some good ensemble acting here, although no one gives a riveting persormance. It's run time of 50 minutes could actually have been trimmed to half an hour show and the episode would not suffer at all. This one is good. It's just not as strong as some of the other entries in the Thriller TV series
For more info check out the episode's entry in IMDB.