This is straight-out a really good psychological-thriller. The protagonist played by Gregory Peck, finds out one day that he doesn't remember the last 2 years of his life, or many other details, what follows is a very convoluted plot where the details of what happened slowly start to unravel, though not in a way that is automatically predictable, I went wrong several times with my guesses and that is always the hallmark of a good mystery film. After watching the film I am of the opinion that not every twist and turn can be easily explained or make logical sense when you finally discover what really happened, why exactly did they pin a murder on him, why did they restock his fridge, when the villains have no idea themselves what has happened to our protagonist, why play Russian roulette with him, why was one of the killers working in the boiler-room, the stairways only make sense if the guy was hallucinating as well. etc. Does this really matter? No not really, most of the film you are playing a guessing game, trying to discover for yourself what exactly is going on and that is good enough for me, the film builds on dramatic tension and the plot is only bad after you watch the film.