He starred in the television series Glory Days and had guest-starring roles in Sex and the City, Dawson's Creek, Haunted, Law & Order: Special Victims Unit, Charmed and Felicity.
Cahill made his feature film debut in 2004 in Miracle, in which he played one of his real life heroes, 1980 U.S. Olympic hockey team goalkeeper, Jim Craig.
In 2000, Cahill appeared in the Off Broadway production of The Altruists.
In 2001, E! Entertainment named him one of its Sizzlin' Sixteen as one of the brightest up-and-coming stars of the year.
Cahill was born and raised in New York.
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