Carole entertained thousands of soldiers during World War 2. In September 1942 she began a five month U.S.O. tour with Kay Francis, Martha Raye, and Mitzi Mayfair. Their group was part of the "Feminine Theatrical Task Force". They went to England, Bermuda, Africa, and Ireland. The group traveled more than 50,000 miles by plane, truck, and jeep. They made 150 personal appearances and performed in 125 shows. Kay introduced the show, Martha told jokes, Mitzi danced, and Carole sang. Her specialty was the song "Strip Polka". The four women became close friends during the tour. Kay was bisexual and developed a crush on Carole. When the girls were in Africa they went through four air raids. They also survived an earthquake and numerous illnesses. Carole had her appendix removed and nearly died from an infection. She lost fifteen pounds while on the tour.
With Mitzi Mayfair and Martha Raye
Carole wrote several magazine articles about her experiences during the war. In 1943 she was asked to write a book for Random House. The title of the book was Four Jills In A Jeep. She told stories about traveling with the other women and performing for the soldiers. Most of the book is about her romance with her husband Tommy Wallace. Carole had the help of a ghostwriter named Edwin Seaver but she wrote the majority of the book herself. She dedicated it "To the Officers and Enlisted Men Who Made Our Tour So Inspiring". In December 1943 Four Jills In a Jeep was serialized in The Saturday Evening Post. When the book was published in the spring of 1944 it sold well and got rave reviews. Before the book had even come out Fox decided to turn Four Jills In A Jeep into a movie. Filming began on October 18, 1943. The movie was directed by William A. Seiter.
With Kay Francis
Carole, Kay, Martha, and Mitzi agreed to play themselves. They were all excited to see their adventures on the big screen. Carole's onscreen romance with John Harvey was based on her real-life relationship with Tommy. The all-star cast included Phil Silvers, Dick Haymes (his film debut), Betty Grable, Jimmy Dorsey, Carmen Miranda, and Alice Faye. Yvonne Wood designed the costumes for the film. Carole was furious when the censors refused to let the actresses wear sweaters. In one scene she wore her own wedding dress. There are numerous songs including "How Blue The Night" and "You'll Never Know". Most of the songs are sung by Dick Haymes. The highlight of the film is Carole singing her only solo number "Crazy Me".
With John Harvey
All of the musical numbers were staged by Carole's close friend Don Loper. Unfortunately Carole and the other actresses had no creative control over the making of Four Jills In A Jeep. The movie ended up being mostly fiction. The plot made their journey seem easy and it completely ignored all of the struggles they went through. Many of the scenes and characters in the movie did not even come from the book. Carole was very unhappy that it turned out to be just a fluffy musical. Four Jills In A Jeep was released on March 17, 1944. The movie was not a hit and a lot of critics panned it. Carole told a friend "I'm afraid the picture hasn't had as good a press as I hoped". Although she had proved she was a talented writer Carole would never write another book.