George Taylor returns from WWII with amnesia. Back home in Los Angeles, while trying to track down his old identity, he stumbles onto a three year old murder case and a hunt for a missing $2 million.

When a music-hall dancer is murdered, a moss rose marks the page of a Bible next to her body. Luckily, another chorus girl saw a gentleman leaving the lodgings. She approaches him directly, saying she'll go to the police if he doesn't meet her demands, but he brushes her off contemptuously. When he learns she's dead serious, he tries to buy her off with a thick wad of pound notes. But it's not money she's after; all she wants is two weeks at his country estate, living the life of a lady.

Mary Scott learns she only has ten months to live before dying of an incurable disease. She manages to keep the news from her husband, Brad and daughter, Polly. She tries to make every moment of her life count, but her effort is weakened by the discovery that Brad is interested in his assistant, Chris Radner. But when she learns that Brad does indeed love her and not Chris, and that Chris is leaving town, she realizes what she must do to ensure the future happiness of Brad and Polly. She persuades Chris to stay, makes a genuine friend of her and watches Polly grow towards Chris.

After WW2, a Los Angeles crime ring uses a complex scheme, involving a freight ship, a junkie, and a corrupt health officer, to smuggle drugs into the USA.

Bumbling detective Stan Laurel disguises himself as a famous matador in order to hide from the vengeful Richard K. Muldoon, who spent time in prison on Stan's bogus testimony.

A seasoned Sargent with a sorry unit, led by an angry 1st Lt., to take out an enemy hold for a convoy to proceed. After their success the Sarge and the crew meet up with another Lieutenant - Female nurse.

A sociologist tries to convince a "bop" singer to switch to calypso, much to the ire of her Hollywood nightclub manager.

A pretty blonde with a Doberman pinscher walks into a bar on April Fool's Day and asks for a bag of bones. Thus begins a merry chase in which a newspaper reporter, a drunken policeman and a hand-painted necktie help locate the missing witness in a criminal investigation.

When You're Smiling is distinguished by the presence of several top recording artists of 1950. The wafer-thin plotline concerns the misadventures of Texan Gerald Durham (Jerome Courtland), who arrives in the Big City to learn the ropes of the music business. Durham not only ends up with a recording contract, but also wins heroine Peggy Martin (Lola Albright) in the bargain. So much for the story. The principal selling card of When You're Smiling consists of the guest-star turns by Frankie Laine, Bob Crosby, The Modernaires, The Mills Brothers, Kay Starr and Billy Daniels.

During Prohibition, a meek bookkeeper hides out from gangsters at a health farm. The gangsters find out where he is. Complications ensue.