Reporters Peter Drante and Conny roam Hamburg’s Reeperbahn at night, uncovering three intertwined tales: Lilli, a aging dancer, searches for her missing husband who once shot her in a jealous rage; multimillionaire Alexander Borgess faces blackmail over past indiscretions; and Karin Thorwaldt seeks Borgess’s aid to secure her fiancé’s acceptance by her conservative father.

Though "blessed" with a complex title, which translates as Marriage with Limited Liability, this German comedy was adapted from the more simply titled stage play Causa Kaiser. Composer Georg Kaiser is unable to secure a divorce from his wife, so he "lives in sin" with his singer-sweetheart Causa. The girl's wealthy uncle dies, leaving her millions -- provided she is married to Georg Kaiser. Hoping to take advantage of a legal loophole, Georg seeks out another man named George Kaiser, intending to marry him off to Causa so that she can collect her legacy. Georg Kaiser # 2 is a middle-aged naif who can't understand why his new bride is so cold to him. When he finds out he's been duped by Kaiser #1, Kaiser #2 finds solace in the arms of another woman closer to his own age, which somehow leads to a happy ending for all concerned.

Balzac adaptation: Escaped convict moves into a brothel where he becomes father to a boy. But his advantageous position is eventually threatened by one of the whores who has fallen in love with the convict's grown up son.

The title alludes to the popular 1925 song I Lost My Heart in Heidelberg composed by Fred Raymond with lyrics by Fritz Löhner-Beda and Ernst Neubach. The film taps into the nostalgic reputation of Old Heidelberg.

The famous singer Roberto Ricci wants to save himself from his overly intrusive female fans with a fake marriage. Mr. Praxl from the marriage institute Eros finds him his own granddaughter Gertie, who works as a waitress and wants to finance her own singing and dancing career with the fee for the role of his wife. To comply with Mr. Ricci's wishes, the attractive Gertie disguises herself as a wallflower with her hair pinned up and high-necked dresses. The act has the desired effect on Roberto's female followers. Over time, however, Gertie and Roberto actually fall in love with each other, which sparks the jealousy of Roberto's stage partner Loretta. With the help of Füllkrug, she tries to thwart the budding romance.