(written from a Production point of view)
Dennis Christopher (born 2 December 1955; age 65) played a Vorta, Borath, in the Star Trek: Deep Space Nine third season episode "The Search, Part II". He later played Danik, a Suliban, in the Star Trek: Enterprise first season episode "Detained".
He's also appeared as Paul Dooley's son in both the film Breaking Away and an episode of Law & Order: Criminal Intent, as well as on recurring roles on Angel (as the evil wizard Cyvus Vail) and Profiler (as the "Jack of All Trades"), and guest appearances on NYPD Blue, Six Feet Under, and Roswell.
In the Profiler series, his character's mother, Miriam Newquay, was played by Louise Fletcher. Furthermore, Dennis Christopher played Dr. Martin Ruper in the Sci-Fi channel's The Lost Room in 2006. He also portrayed Eddie Kaspbrak in the 1990 adaptation of Stephen King's It.
Between 2000 and 2001, Christopher portrayed Vince Elsing in the short-lived mystery/science fiction series FreakyLinks where he worked with Ron Canada, Patrick Fabian, Daniel Roebuck, Ryan Bollman, John Billingsley, Connor Trinneer, Leslie Jordan, Brooke Benko, Dawn Stern, Art Chudabala, Steve Vinovich, Faran Tahir, Aaron Lustig, Scott Lincoln, Mirron E. Willis, and Tom McCleister.
In the 1980s, he guest-starred on The Equalizer as Father Nicholas Kostmayer, a Catholic priest and younger brother of series recurring character Mickey Kostmayer, played by Keith Szarabajka. It was during December of 2012, Dennis could be seen in the Quentin Tarantino motion picture Django Unchained as Leonide Moguy.