At the start of the film, everything is rosy, full of natural light fresh air and pristine waters as painter Geoffrey Carroll (Bogart) and his new love, Sally Morton (Stanwyck) are vacationing in the mountains on a fishing vacation. It's all hearts and flowers and the two are very much in love, Gerry paying less attention to the fish than in sketching Sally. But, a sudden squall puts a damper on things when, while giving Sally a protecting coat, a letter falls out of his pocket, addressed to Gerry's wife. Sally is shocked and breaks off the affair.
Gerry explains the situation. The letter is to ask his wife for a divorce. She has been an invalid since the birth of their child, and her estate will supply all the care she needs. But, the first Mrs. Carroll dies, Gerry continues to pursue Sally, they marry and she moves in with Gerry and his daughter, Beatrice.
Gerry is distant, locking himself in his studio to paint for hours on end. They argue about sending Gerry's daughter to a boarding school, which she does not want to go to, preferring to stay at home with Gerry and Sally. Sally talks to Beatrice (Ann Carter), who reveals that the first Mrs. Caroll was hardly an invalid, but actually quite healthy and died suddenly after Gerry had returned from a fishing trip (DUN-dun-dunnn) and finished his portrait of her as an angel of death.
This naturally freaks Sally out, especially after finding the key to Gerry's studio and seeing that he's working on a portrait of her as an angel of death. Plus, Gerry is being very interested in a vampiric young socialite (Alexis Smith), who has commissioned Gerry to paint her portrait—maybe she should just wait a while.
The chief enjoyments of The Two Mrs. Carrolls is the pairing of Bogart and Stanwyck, a truly unhinged performance by Bogart—he has a wonderful final line—and the generally creepy air permeating the film, even when it becomes ludicrous. Beyond that, there's not much there.