Marcus Frank Harelik (born June 5, 1951) is an American television, film, and stage actor, and playwright.

Harelik has played parts on the television series Seinfeld, Numbers, Wings, Grace Under Fire, Will & Grace, NCIS, Boy Meets World, Breaking Bad, Bones, Six Feet Under and five episodes of the first season of The Big Bang Theory as Dr. Eric Gablehauser.

[9] He has appeared in several other plays including Temptation (1989),[10] The Heidi Chronicles (1991),[11] Elmer Gantry (1991),[12] Tartuffe (1999),[13] Old Money (2000),[14] The Hollow Lands (2000),[4] Be Aggressive,[15] The Beard of Avon (2001),[16] Cyrano de Bergerac (2004).

[4] Harelik also played Dr. Paul Stickley in HBO's series Getting On, an American adaptation of the British sitcom of the same name.

[6] In 2015, Harelik co-starred as Jamie Thompson's father in This Isn't Funny, and in 2017, he played baseball player Hank Greenberg in the film Battle of the Sexes.