Glenn was born in Park Ridge, Illinois and raised in Hayward, California. At early age he joined the American Conservatory Theater Company and later the Drama Studio London. Glenn received a Drama Logue Award nomination for his performance in the play Cybeline and continued his stage career with performances at the Oregon Shakespeare Festival before he attended New York University's Tisch School of Arts. Beside acting, writing, directing, and producing, Glenn, a skilled mountaineer, was part of the 1998 Annapurna I South Face Expedition and the 2004 Everest Friendship Beyond Borders Expedition.