Gangster Harry "Silky" Fellowsby is being treated for an unknown ailment at the Fulton Hospital by Dr. Bill Burns, though nurse Peggy Osborne tells the physician that she thinks his patient is "faking." Peggy is right, as Silky is hiding in the hospital while making plans to rob the City National Bank across the street. Phil and Buster, Silky's gangster pals, are itchy to rob the bank, but Silky insists that they wait until "the boys from Detroit" arrive to assist them. Meanwhile, Bill runs into his old childhood friends, Flash Fulton and Weejie "Tubby" McCoy, who are now working as sidewalk photographers. Hoping to get newspaper jobs, Flash and Tubby tag along with Bill on an ambulance call to a fire. When Tubby falls off a fire truck ladder and ends up in Bill's hospital, he and Flash are mistaken by Silky and his gang for their Detroit compatriots. The next day, Silky and his gang rob the bank, and the naïve photographers take the blame. During the robbery, Peggy discovers Silky missing, but the gangster returns to his room before Bill arrives. Silky then convinces Bill to take him to Sun Valley, Idaho, where Bill has been hired as the resident physician at a resort. In order to protect their alibi, the gangsters also hire Peggy to be Silky's private nurse. Flash and Tubby get on the same train to Sun Valley, and Tubby immediately falls in love with Marcia Manning, a singer with Johnny Long's band and an old acquaintance of Silky. Once at the Sun Valley resort, Flash and Tubby get jobs as waiters, and Tubby attempts to impress Marcia by pretending to be a pianist, with disastrous results. Flash and Tubby then meet with Silky and his gang, and the photographers convince the gangsters that they have pictures of them robbing the bank. Silky initially agrees to pay Flash and Tubby $25,000 for their negatives, but then has Marcia attempt to seduce Tubby into giving her the photos. Later, Flash tells Bill that Silky and his gang robbed the bank, so the physician tries to send Peggy home, but she is abducted by the gangsters when she attempts to leave. Silky and his gang then decide to move to a mountain hideout, but Flash and Tubby take a dogsled and get there first. Hiding in a tree, the photographers watch as the gangsters arrive with their captives, Peggy, Bill and Marcia, then pretend they have guns in order to force Silky to pay them "their cut" for the robbery. After sending Bill and Peggy for the police, Flash and Tubby fight with the gangsters, and with Marcia's help, manage to escape on skis with the money. The gangsters give chase, but are captured by the police. When Marcia praises Tubby as a hero, he assumes she is going to marry him, but she breaks his heart by telling him that she has married Johnny in a double wedding ceremony with Bill and Peggy. As Tubby then prays to be hanged if he ever falls in love with another girl, he is caught in the neck by a train's mail hook when he ogles an attractive young lady.