She was raised in New Mexico and Oklahoma, moving to Toronto in 1995 after her television debut starring in an episode of The Outer Limits titled "The New Breed".
[1] She later made her film debut starring in Joe's Wedding (1996) and later appeared in feature and made-for-television films such as Elvis Meets Nixon (1997), Finding Graceland (1998), Escape from Mars (1999), Waydowntown (2000), Love and Murder (2000), And Never Let Her Go (2001), Danger Beneath the Sea (2001), Salem Witch Trials (2002) and America's Prince: The John F. Kennedy Jr. Story (2003).
[2] From 2001 to 2008, Isbell starred in the Showcase soap opera, Paradise Falls, for which she was nominated for a Canadian Screen Award for Best Actress in a Continuing Leading Dramatic Role.
[1][3] She made guest-starring appearances on both Canadian an American television series such as The Eleventh Hour, Murdoch Mysteries, ReGenesis, Republic of Doyle, Flashpoint, Nikita, Suits, Rookie Blue, Saving Hope, Rogue, Designated Survivor and Anne.
In 2024, Isbell was cast in the Citytv police drama series, Law & Order Toronto: Criminal Intent playing Detective Alice Riley.