(written from a Production point of view)
Earl Boen (born 7 November 1941; age 79) played Nagilum in the Star Trek: The Next Generation second season episode "Where Silence Has Lease". He has also provided voices to characters in Star Trek computer games, including Star Trek: Voyager - Elite Force and Star Trek: Bridge Commander.
Boen is best known for playing Dr. Peter Silberman in The Terminator (1984), Terminator 2: Judgment Day (1991) and Terminator 3: Rise of the Machines (2003). Besides Arnold Schwarzenegger, he is the only actor to appear in the first three Terminator films. Boen appeared with Paul Winfield, Dick Miller and Brian Thompson in The Terminator, Nikki Cox, Jenette Goldstein, Castulo Guerra, Terrence Evans and Abdul Salaam El Razzac in Judgment Day, and Kristanna Loken, David Andrews, Eric Ritter, and Carolyn Hennesy in Rise of the Machines. On the television series The Terminator: The Sarah Connor Chronicles, Silberman was portrayed by Bruce Davison.
Other film credits include the science fiction comedy The Man with Two Brains (1983, with James Cromwell, David Warner and Jeffrey Combs), the drama Walk Like a Man (1987, with Christopher Lloyd, Megan Parlen, John McLiam, Beau Billingslea, and Ellen Albertini Dow), and the comedy Chopper Chicks in Zombietown (1989, with Lycia Naff, Rob King, and Dennis Madalone).
He is also famous for voicing the main villain of the Monkey Island series of games: the undead pirate LeChuck. Among his animation roles, he provided the voice of Señor Senior, Sr., a character originated by Ricardo Montalban, for four episodes of the Disney series Kim Possible when Montalban wasn't available. And for several years in the early 2000s, he was the voice of Mr. Bleakman, the irascible neighbor to the Howard family on the PBS Kids series Clifford the Big Red Dog.