Payne plays Eddie Driscoll, a washed-fighter who watches his career-ending defeat (the bout was stopped due to cuts) on TV while his wife impatiently puts dinner on the table. Wifey (Peggie Castle) wants more from life than a cabbie can provide, and is willing to risk a lot to get it. Insulted and humiliated by the missus, Eddie's bad night is only beginning. Getting back some money he lent to an actress friend (Evelyn Keyes) is small consolation, and nearly forgotten when Eddie goes to pick the wife up from her flower shop job and finds her smooching another man. He's in no mood to be helpful when Linda, the actress, meets him again and begs for his help, but when she says she's killed a man he feels he has no choice but to help. She takes him to the theater, shows him the corpse, and goes into a suspiciously elaborate account of her fatal encounter. It's suspicious because you suspect that Linda must be crazy, but it's really suspicious because it's a set-up. Once Eddie agrees to help her dispose of the body -- psyche! -- it turns out that she was auditioning for the producers, proving that she's so good in her theater role that she can make a dumb lug like Eddie believe her and want to help a killer. Eddie doesn't appreciate the art of it and starts slugging theater people. There's no hard feelings from the show folks, though; they only want to have him arrested in order to stir up publicity for the play.
By this point, 99 River is shaping up as a "night from hell" picaresque of the sort that became more common starting in the 1980s, with an added element of tension in Eddie's mounting rage. His frustration and anger at being manipulated for a joke, his sudden desire to fight again because all he really knows how to do is hit people, make him a real menace to Linda when she runs to his department to beg forgiveness. He's packing to leave town, not only to quit his marriage but because that frivolous arrest warrant could mean hard time for him; as a boxer, his fists are registered weapons, so he won't just get fined as Linda believes. He barely restrains himself from beating her up, but she's determined to follow him out the door and into his cab, only to share his shock when he opens the car door and finds his wife's corpse inside.
Viewers are probably taken in as easily as John Payne is by the sinister set-up for 99 River Street's disorienting practical joke, delivered by Evelyn Keyes.
Mrs. Driscoll had become the accomplice of her lover, Rawlins (Brad Dexter) but had become an impediment to negotiations between Rawlins and his fence. Knowing the score between the Driscolls, Rawlins contrives a way to get the woman out of the way and frame Eddie. The theater contretemps is forgotten as Eddie now must find Rawlins to clear his name without getting killed along the way, by Rawlins or the fence's goons, who think he's Rawlins's accomplice. Linda determinedly tags along, ultimately taking a reckless chance on her thespian talent to lure Rawlins into a trap, little knowing that a more lethal trap has been set for Rawlins and anyone involved with him....
Here's a trailer from TCM.com