Glenn Quinn

Glenn Martin Christopher Francis Quinn (May 28, 1970 – December 3, 2002) was an Irish actor. He was best known for his portrayal of Mark Healy on the popular '90s family sitcom Roseanne. Quinn also amassed a large fan base for his portrayal of Doyle, a half-demon, on Angel, a spin-off series of Buffy the Vampire Slayer.

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