Filmmaker Peter McCarthy was randomly attacked on a night out in Galway, which left him badly scarred and with compromised vision in his left eye. On his recovery, Peter came across an article on Muay Thai boxing in a newspaper and decided to leave Ireland for Thailand and learn how to defend himself. This documentary charters Peter's journey over a year and a half in Thailand, as he fights in semi-professional bouts in arenas full to capacity around Thailand. Through the course of his experiences in Muay Thai, Peter learns that behind his compulsion to fight lies fear and ultimately a deep-seated anger that has driven him to risk his body in the ring. Fight or Flight is a compelling first person account of Peter's journey as he tries to come to terms with the deep-seated anger within him.