(written from a Production point of view)
Michael "Mike" G. Hagerty (born 10 May 1954; age 65) is an actor who has appeared twice on Star Trek: The Next Generation. He portrayed Klingon Captain Larg in the fifth season episode "Redemption II" and Skoran in the seventh season episode "Thine Own Self". Hagerty also appeared as the bartender in the 1996 video game Star Trek: Klingon. Hagerty filmed his scene for "Redemption II" on Wednesday 17 July 1991 on Paramount Stage 16. His costume from the episode "Thine Own Self" was later sold off at the It's A Wrap! sale and auction on eBay. 
Born in Chicago, Illinois, Hagerty graduated from the University of Illinois and is today living in Los Angeles, California.
He is perhaps best known outside of Star Trek for his frequent appearances as Mr. Treeger on the hit television sitcom Friends. Hagerty also made an appearance in the 1990 comic adaptation Dick Tracy, as did fellow Trek alumni Hamilton Camp, Seymour Cassel, Robert Costanzo, Ed McCready, Colm Meaney, Michael J. Pollard, Bert Remsen, John Schuck, Paul Sorvino, and Ian Wolfe. Hagerty appeared in films such as Brewster's Millions (1985, with Stephen Collins), Red Heat (1988), One Good Cop (1991, with Kevin Conway and Tony Plana), Wayne's World (1992), Speed 2: Cruise Control (1997), Austin Powers in the Spy Who Shagged Me (1999, with Clint Howard), and Inspector Gadget (1999, with Rene Auberjonois and Andy Dick).
Hagerty had the supporting role as Mike in the HBO sitcom Lucky Louie (2006-2007), where he performed along Pamela Adlon. Hagerty appeared in guest roles in the television series Boston Legal (2007, with regulars Rene Auberjonois and William Shatner, and guest stars Mark L. Taylor, Lawrence Pressman, and Billy Mayo), Entourage (2007), Ghost Whisperer (2007), CSI: Crime Scene Investigation (2008), and Monk (2009).
More recent work includes guest roles in Medium (2010), Good Luck Charlie (2010), Glee (2010), and Happy Endings (2011) and had a supporting part in the television drama A Christmas Wish (2011).