HBO comedy Entourage has added several guest castings, including Matt Letscher, William Fichtner and Scott Caan for multiepisode arcs on the series' upcoming sixth season, according to The Hollywood Reporter.

Eli Stone alum Letscher plays Dan Coakley, a handsome, arrogant TV studio executive who oversees Drama's (Kevin Dillon) TV series.

Prison Break co-star Fichtner plays Phil Yagoda, a slick TV producer who had a hit teen series in the 1990s and is trying to remake it with Drama.

Caan plays Scotty Lavin, a cocky and highly competitive manager who acts tough and trash talks to cover up how insecure he is and sees E (Kevin Connolly) as a threat.