Jay, who died of natural causes on Saturday, appeared in 10 episodes of Deadwood's first season, playing card sharp Eddie Sawyer. He also co-wrote one of the Season 1 Deadwood episodes with David Milch. But Deadwood wasn't his only HBO work. He also starred in the David Mamet-directed one man Broadway play Ricky Jay and His 52 Assistants, which was filmed for HBO. "Master magician and historian Ricky Jay has passed away," tweeted fellow magician Neil Patrick Harris. "The breadth of his knowledge and appreciation for magic and the allied arts was truly remarkable. Such sad news, such a profound loss."