There is no doubt that Alfred Hitchcock was a seriously talented director. Many of his films are undeniable classics that have stood the test of time and are highly watchable to this day. This list could include The 39 Steps, Rear Window, North by Northwest, Dial M for Murder, Vertigo, The Birds, Shadow of a Doubt, and a few other films.
However, "Suspicion" is not aging well at all and is really so unwatchable that it seems to me that it was probably a bad film even by 1941 standards. The list of scenes that work well could be listed on a matchbook with a crayon. The script is loose and ridiculous most of the time, but the acting seems so forced and wooden and borderline amateurish throughout, that it is almost unbelievable. Joan Fontaine tries to shore things up but she is on a slippery slope and Cary Grant doesn't provide much assistance. His acting is so bad at times that I have seen better performances in high school plays or college Theatre Experience classes where a Chemical Engineer is acting for the first time with no formal training.
After about 30 minutes of watching this film you may find yourself reaching for the DVD sleeve in the dark to see if you accidentally picked up some kind of special edition version that was cobbled together without any editing.
The subject matter is serious, yet the film has a silly and trite feel to it that just seems so out of place you become numb with perplexity.
"Suspicion" is basically unwatchable and another very very very overrated BAD movie.