Major Dad is a family friendly sitcom centered on a straitlaced Marine, his wife and stepdaughters, and his fellow Marines.The first season is set at the fictional Camp Singleton (meant to represent Camp Pendleton) where hard charging United States Marine Corps Major John D. "Mac" MacGillis is commander of the infantry training school's acquisition division. MacGillis's life is changed when he falls in love with a liberal journalist, Polly Cooper. The show follows Mac in his work life—where he deals with Lt. Eugene Holowachuk, Sgt. Byron James and Merilee Gunderson – as well as his home life as he learns to live with Polly's three daughters, Elizabeth, Robin, and Casey.At the beginning of the second season, the MacGillis family moves to Camp Hollister (based on Marine Corps Base Quantico) where Mac must adapt to the role of Staff Secretary and the crazy antics of Commanding General Marcus C. Craig, Aide-de-Camp 1st Lt. Eugene Holowachuk (who transferred with Major MacGillis from Camp Singleton), and Gunnery Sgt. Alva "Gunny" Bricker.