Gregory Everett "Greg" Proops (born October 3, 1959) is an American actor, stand-up comedian and television host. He is widely known for his guest appearances on the U.K. and U.S. versions of Whose Line Is It Anyway?. He has also voiced the titular character on the U.S. version of Bob the Builder. Early life Proops was born in Phoenix, Arizona, and raised in San Carlos, California, a suburb south of San Francisco, attending San Carlos High School. He attended the College of San Mateo and spearheaded the comedy duo "Proops & Brakeman". Later, he took courses in improvisation and acting at San Francisco State University, though he never finished college. Career Improv comedy After college, he joined an improv group with Mike McShane. Both Proops and McShane impressed producers Dan Patterson and Mark Leveson, who put them on their show, Whose Line Is It Anyway?. He frequently instigated jokes concerning various idiosyncrasies and differences between British English and American English, and would frequently banter with Clive Anderson on these matters (among others). He lived in London for four years when he was doing the show and lists McShane, Richard Vranch and Colin Mochrie among his best friends. After the show ended, he was recalled for the American version and has been a frequent "fourth contestant". Through 2020, he has appeared in 74 U.S. Whose Line episodes, more than any other non-regular cast member. Proops also appeared in every episode of the short-lived Drew Carey's Green Screen Show, where the performers would play improv games (some of which were taken from the show's main influence Whose Line Is It Anyway?) in front of a massive green screen. Later, animators would draw on the background and other props. In April 2011, Drew Carey's Improv-A-Ganza premiered on GSN featuring Proops along with other frequent guests from Whose Line is it Anyway? In July 2012, Proops appeared in ABC's improvisation show, Trust Us with Your Life. In November 2011, Proops did a week on Royal Caribbean's Freedom of the Seas with the Lewis Black Comedy Cruise Tour. He performed the entire week of stand-up with other artists, which included a live, one-hour podcast in front of his entire audience. Film and television Proops has performed his stand-up act across Britain, mainland Europe, Australia and New Zealand. His other credits include hosting Space Cadets, a mid-1990s science-fiction comedy game show on Channel 4 in the