This from USA Today

 Powers Boothe, the character actor known for his villain roles in TV's Deadwood, and in the movies Tombstone, Sin City and The Avengers, has died. He was 68.

Boothe's publicist says he died of natural causes at his home in Los Angeles Sunday.

I recall in the early '80s he reprised the roll of Phillip Marlowe he did for HBO.Great Actor - RIP