Here's a few more.
1) At age 41 when World War II started I was exempt from the draft. Still I left a $30,000 a month job, enlisted in the Army as a private and worked my way up through the ranks. After graduating Officers' Candidate School in 1942 I attended aerial gunnery school, then served with the 8th Air Force in England. Though I flew combat bombing missions, my primary job was photographing other airmen in action for a movie to recruit airmen for the war effort. I completed my service as a major.
Clark Gable.
2) At the start of WWII I left a Hollywood career to work in a circus in Mexico, gathering intelligence for US Naval Intelligence. After enlistment in the Navy, I served at Tarawa on an amphibious attack transport, where I was conspicuous for transporting dozens of wounded Marines under fire. Decades later my WWII actions were recognized with a belated award of the Bronze Star with combat "V".
Eddie Albert
3) My celebrity status didn't help my efforts to join the Navy when WWII began; the Navy found me underweight? After "plumping up" I joined the Army Air Force and flew 20 combat missions during which I earned the Distinguished Service Medal, two Distinguished Flying Crosses, and four Air Medals. After retiring as a Brigadier General in the Air Force Reserves, I was also awarded the Presidential Medal of Freedom.
Jimmy Stewart
4) I left my successful movie career in 1942 to become a Marine Corps pilot, logging more than 1,000 hours flight time before the war ended. I am remembered by many of the Marines who served at Iwo Jima, where I flew supplies in and ferried wounded men out.
Tyrone Power
5) The tail gunner on a bomber was forced to defend his aircraft from within a tiny, cramped cubical from a virtually prone position. I flew 21 combat missions in World War II, most as a tail gunner. I also flew five weather observation missions.
Charles Bronson