Career
Costelloe, a former NYFD firefighter, died of a self-inflicted gunshot wound on December 16, 2008, at the age of 47. His body was found two days later at his home in Sunset Park, Brooklyn. Friends and family were surprised by his death, and at a loss for answers about its cause.
Shortly before his death, Costelloe had been playing a hustler in the hit ensemble play Gang of Seven.