Robert Martin Culp (born August 16, 1930) is an American actor and scriptwriter, perhaps best known for his work in television . Culp earned an international reputation for his role as Kelly Robinson on I Spy (1965-1968), the espionage series, where he and co-star Bill Cosby played a pair of secret agents and for playing Ray Barone's father-in-law on Everybody Loves Raymond . After his series ended in 1959, Culp continued to work in television, including a guest-starring role as Stewart Douglas in the 1960 episode "So Dim the Light" of CBS's anthology series, The DuPont Show with June Allyson . He appeared too on the NBC anthology series, The Barbara Stanwyck Show . Moreover, Culp was cast as Captain Shark in a first season episode of NBC's The Man from U .N.C.L.E. (1964). Among his more memorable performances were in three episodes of the science-fiction anthology series The Outer Limits (1963-1965), including the classic "Demon with a Glass Hand", written by Harlan Ellison. In the 1961-1962 season, he guest starred on ABC's crime drama Target: The Corruptors!. In the 1962-1963 season, he guest starred in NBC's modern Western series Empire starring Richard Egan. In the episode, he got into a boxing match with series co-star Ryan O'Neal. In 1981 he got his big break back into the television realm when he starred in The Greatest American Hero, he played tough-as-nails-by-the-book-FBI Agent Bill Maxwell who gets teamed up with a special education teacher named Ralph Hinkley after Ralph receives a supersuit with special powers from aliens delivered by a flying saucer. That show only lasted three years ending in 1983 but the character of Bill Maxwell will always be remembered by some Culp fans. He reprised the role in a voice-over role on the stop-motion sketch comedy Robot Chicken. .