![Luke](https://static.hbo.com/content/dam/hbodata/series/in-treatment/character/luke-1920.jpg?w=1200)
Luke
Played by Russell Hornsby
Oliver's gregarious father is frustrated with his soon-to-be ex-wife's overprotective treatment of their son, but when it's his turn to play parent, he makes his share of mistakes that alienate Oliver and infuriate Bess.