Actor. He is best remembered for his reoccurring portrayal of the inquisitive Professor Mayberry on the sitcom "Rocky Jones, Space Ranger." Born Matthew Cassan, after attaining his degree in theatrical arts from the Royal Academy in London, England, he began his career on the stage appearing as a leading man in such productions as "David Copperfield" and "Romeo and Juliet." Upon immigrating to the United States in 1914, he settled in New York City, New York, and became a prominent headliner on Broadway and was discovered by director Alan Crossland during a production of "Mr. Prim Passes By". Impressed by his articulate voice, manly stealth, and blonde good looks, he arranged for him to begin a career in the film industry beginning with him being under his supervision in "The County Cousin" (1919). From there, he would go on to enjoy a successful career as a character actor appearing in over 100 features; often typecast as husbands, fathers, doctors, sidekicks, henchmen, villains, heroes, historical figures, noblemen, medics, jurors, politicians, curmudgeons, playboys, love interests, businessman, retail clerks, educators, white-collared workers, stock traders, cowboys, policemen, sheriffs, butlers, doormen, chauffeurs, clergymen, foreigners, adventurers, detectives, reporters, landlords, neighbors, historical figures, military men, and patriarchs. He appeared in such feature films as "Piccadilly Jim" (1920), "Classmates" (1924), "White Mice" (1926), "The Nest" (1927), "Sweet Sixteen" (1928), "The Green Goddess" (1930), "Partners on the Trail" (1931), "Lost in Limelight" (1933), "The House of Rothschild" (1934), "Becky Sharp" (1935), "The White Angel" (1936), "Another Dawn" (1937), "The Adventures of Robin Hood" (1938), "Gunga Din" (1939), "Vigil in the Night" (1940), "The Lady Eve" (1941), "Random Harvest" (1942), "Bomber's Moon" (1943), "Wilson" (1944), "My Name is Julia Ross" (1945), "Devotion" (1946), "If Winter Comes" (1947), "Kiss the Blood Off My Hands" (1948), "Prison Warden" (1949), "The Rogue of Sherwood Forest" (1950), "Young Bess" (1953), "D-Day the Sixth of June" (1956), and "The Story of Mankind" (1957). During the advent of television, he flourished as a household name appearing in various guest spots on such syndicated sitcoms as "The Adventures of Jim Bowie," "Studio 57," and "Four Star Playhouse." During his career, he was an honorary member of Actors Equity, was a member of the Screen Actors Guild, was supportive of the Motion Picture and Television Fund, had been a regular parishioner of the Episcopal church, was an active member of the Hollywood Democratic Committee, presided as a chairman for his local charters of the American Red Cross and the March of Dimes, was a naturalized United States Citizen, and he was married to liberal arts instructor Louise Van Loon from 1927 until his death (their union produced three children, two of whom were film and television actors Johnny and Billy Sheffield). After appearing in what would be his final role in "The Buccaneer" (1958), Sheffield died at his suburban home from the complications of a heart attack.