Actor. He is best remembered for his recurring portrayal of the warmhearted patriarch Walter Powell on the sitcom "Charles in Charge". Born into a traditional working-class family, after serving in the United States Army during the Korean War, upon returning to civilian life, he attained his degree in theatrical arts under the G.I. Bill from the University of Washington and began his career appearing as a leading man in stock companies. While appearing in a stage production of "The Philadelphia Story" in Stockton, California, he was discovered by director Jean Yarbrough who happened to be an audience attendee one fateful evening. Impressed by his reddish good looks, slim physique, and distinctive voice, he took notice of his potential and arranged for him to settle in California and begin a newfound career in the film industry beginning with him appearing under his supervision per a supporting role in two episodes of "Flight". From there, he would go on to flourish as a notable character actor appearing in over 160 features; often typecast as soldiers, sailors, authority figures, doctors, blue-collared guys, detectives, reporters, cowboys, sheriffs, husbands, fathers, boyfriends, policemen, city slickers, sergeants, clergymen, businessmen, politicians, lieutenants, retail clerks, educators, eccentrics, landlords, curmudgeons, kindly neighbors, and judges. He appeared in such feature films as "Battle of the Coral Sea" (1959), "Man on a String" (1960), "The Walking Target" (1960), "The Honeymoon Machine" (1961), "Experiment in Terror" (1962), "Mosby's Marauders" (1967), "A Man Called Gannon" (1968), "Tropic of Cancer" (1970), "Lady Sings the Blues" (1972), "Outlaw Blues" (1977), "Cloud Dancer" (1980), "Return of the Living Dead III" (1993), "Midnight Man" (1995), "Every Dog Has Its Day" (1998), "Extreme Honor" (2001), and "The Stranded" (2007). On television, he flourished as a household name appearing in numerous guest spots on such syndicated sitcoms as "The Californians," "Steve Canyon," "Dennis the Menace," "Bourbon Street Beat," "Not for Hire," "Death Valley Days," "Manhunt," "Two Faces West," "National Velvet," "The Jim Backus Show," "Route 66," "The Detectives," "Have Gun - Will Travel," "General Electric Theatre," "G.E. True," "Stoney Burke," "Empire," "Combat!," "The Eleventh Hour," "Dr. Kildare," "The Twilight Zone," "My Favorite Martian," "Ben Casey," "Profiles in Courage," "12 O'Clock High," "The Fugitive," "Adam-12," "The Governor & JJ," "Cade's County," "Marcus Welby, M.D.," "Love, American Style," "M*A*S*H," "The Magical World of Disney," "Barnaby Jones," "The Practice," "Cannon," "CPO Sharkey," "The Rockford Files," "Black Sheep Squadron," "ABC Weekend Specials," "The Ropers," "Bosom Buddies," "Insight," "Lou Grant," "Alice," "Simon & Simon," "Benson," "Too Close for Comfort," "Tales of the Gold Monkey," "Quincy M.E.," "Condo," "Remington Steele," "Automan," "Fame," "The A-Team," "Knight Rider," "Alfred Hitchcock Presents," "It's a Living," "Hollywood Beat," "Newhart," "Amazing Stories," "Highway to Heaven," "Doogie Howser, M.D.," "Dallas," "Good Advice," "The Golden Girls," "Picket Fences," "Promised Land," "Caroline in the City," "ER," "Medium," "7th Heaven," "Cybill," and "Chicken Soup for the Soul". During his career, he was a member of the Screen Actors Guild, was supportive of the Motion Picture and Television Fund, was a regular parishioner of the Catholic church, had been supportive of the California State Democratic Committee, was the celebrity spokesman for the United States Postal Service, had been a theatrical instructor for the Pasadena Playhouse, was one of the founding members of the Canyon Theater Guild, and he was married to public relations advisor Peggy Cannon from 1994 until his death (their union produced no children). Following his final appearance in "Born" (2007), Callahan, a lifelong smoker, died from complications of esophageal cancer.