Melvin Douglas and Jackie Cooper co- star with Deanna Durbin in this comedy about romance and teenage infatuation. Durbin had already reached stardom by age 16, and she plays teenager Alice Fullerton who gets a crush on an older man. That's Douglas's Vincent Bullitt, a top-notch ace reporter and journalist for her father's big New York newspaper.
Bullitt was wounded covering the Spanish Civil War and has come home for a rest. Publisher Gilbert Fullerton (played by John Halliday) wants him to relax and stay at his country home while writing a series of articles on the political scene in Europe. But, Alice's youth group has moved into the family guest quarters where they are rehearsing for a benefit play. Alice has to come up with a plot for them to chase Bullitt away, and they carry it out initially. But as she starts to fall for Bullitt, the story takes a turn with a couple of twists that lead to family turmoil and some more humor.
Jackie Cooper plays Ken Warren, who is directing the play and is himself smitten with Alice. While not a true love triangle, the story has the characters in positions that lend to good humor along those lines. In the meantime, Gilbert and Mrs. Fullerton (played by Irene Rich) get involved and stumble through the teenage infatuation of their daughter. A young Juanita Quigley plays Cooper's little sister, The Pest, whom he calls Butch once or twice; and she has a couple of funny scenes.
This was one of the films that helped Deanna Durbin's star rise and stay up through her short career which she ended just 10 years later. The plot is strictly comedy romance, with the music and Durbin's singing interspersed. But that did contribute to "That Certain Age" receiving two Oscar nominations - for sound recording and original song.