Suspicion (1941) is a romantic psychological thriller directed by Alfred Hitchcock, and starring Cary Grant and Joan Fontaine as a married couple. It also stars Sir Cedric Hardwicke, Nigel Bruce, Dame May Whitty, Isabel Jeans, Heather Angel, and Leo G. Carroll. Suspicion is based on Francis Iles's novel Before the Fact (1932). Wikipedia
Johnnie Aysgarth: (to Lina) I think I'm falling in love with you, and I don't quite like it.