William Joseph Devane is an American actor. He is known for his role as Greg Sumner on the primetime soap opera Knots Landing (1983–1993) and as James Heller on the Fox serial dramas 24 (2001–2010) and 24: Live Another Day (2014). He is also known for his work in films such as Family Plot (1976), Marathon Man (1976), Rolling Thunder (1977), Payback (1999), and Space Cowboys (2000).

Knots Landing is an American primetime television soap opera that aired on CBS from December 27, 1979, to May 13, 1993. A spin-off of Dallas, it was set in a fictitious coastal suburb of Los Angeles and initially centered on the lives of four married couples living on a cul-de-sac, Seaview Circle. Throughout its 14-year run, storylines included marital strife, rape, murder, kidnapping, assassinations, drug smuggling, politics, environmental issues, corporate intrigue, and criminal investigations. By the time of its conclusion, it had become the third-longest-running primetime drama on U.S. television after Dallas, Gunsmoke, and Bonanza and the last scripted primetime drama show that debuted in the 1970s to leave the air.