Former radio singer Kay learns from her gossipy friends that her husband, Steve, has had an affair with chorus girl Crystal. Devastated, Kay tries to ignore the information, but when Crystal performs one of her musical numbers at a charity benefit, she breaks down and goes to Reno to file for divorce. However, when she hears that gold-digging Crystal is making Steve unhappy, Kay resolves to get her husband back. The Opposite Sex is a remake of the 1939 comedy The Women.
Jeanne Dante stars as precocious 13-year-old Judy Widdell, a devoted fan of dime-novel detective stories. When a real murder occurs in the vicinity, Judy insists upon playing sleuth, dragging teenaged astronomer Tom Fenton (Kenneth Howell) into her Sherlock shenanigans.