Suspicion

I'm on a Hitchcock spree. Suspicion is supposed to be one of his best, and after having watched it, I agree.

Warning: spoilers.

I like movies that play with genre conventions, or switch genres. Watching Suspicion, you can't tell whether Cary Grant is a bad guy and a murderer, or a good guy and not a murderer. So we think it's thriller or maybe a psychological thriller.

As it turns out, he's not a murderer, but he is a bad guy (redeemed by the love of a good woman), so the movie turns out to be a melodrama. Nicely played, Hitchcock!

Unbeknownst to me beforehand, Suspicion is also a landmark in the portrayal of LGBTQ characters (the following is an excerpt from Great Moments in Gayness: "Suspicion"):
Johnnie (Cary Grant) and Lina (Joan Fontaine) visit Johnnie's friend Isobel, a writer of murder mysteries. Also attending dinner is Phyllis. Based on their familiarity and the way they serve dinner, it is obvious the two women live together. Moreover, while Isobel ("Izzy") dresses as a British lady should, Phyllis ("Phil" to her partner) is in a man's suit and tie, with a man's hairstyle  
And this is what's so glorious. Phil and Izzy aren't dangerous. They're not villains. 
They're not the subject of a joke, nor exaggerated, nor horrifying. They simply are. A butch/femme couple, in 1941, relaxing at home, entertaining a straight couple, chatting about books. Fifty years later, Basic Instinct inspired protest from the LGBT community, because it was still almost impossible to see gays and lesbians in a movie unless they were killers or crazy, suicidal or deranged or tragic or pornified, or—best case scenario—the wacky sexless neighbor. 
Phil and Izzy are just an ordinary gay couple. They're not in the movie because they're gay, and their gayness is never mentioned. That they're butch/femme—probably the least-represented type of queer couple in the media—just adds to my pleasure.