[3] He is best known for portraying Johnny "Drama" Chase on the HBO comedy series Entourage,[4] Bunny in the war film Platoon, and John Densmore in the musical biopic The Doors.

[8] He is the son of Mary Ellen, a homemaker, and Paul Dillon, a portrait painter, sales manager, and golf coach at Fordham University.

Other notable film roles from that period included War Party (1988), No Escape (1994), and The Doors (1991) in which he played drummer John Densmore.

He appeared in the family comedy film Hotel for Dogs (2009) which collected $117 million at the worldwide box office.

In 2011, Dillon appeared in the CBS comedy sitcom How to Be a Gentleman portraying Iraq war veteran Bert Lansing.

[16][17] Entourage cast member Jerry Ferrara was his best man and Kevin Connolly, another series co-star, walked Stuart down the aisle after Dillon shouted "Victory!"

[19] The divorce was finalized in November 2019, and Dillon was ordered to make equalization payments to Stuart totaling $1,705,594 and an additional $242,411 for her share of a brokerage account.