James Gunn was born and raised in St. Louis, Missouri, to Leota and James Francis Gunn. He is from a large Catholic family, with Irish and Czech ancestry. His father and his uncles were all lawyers. He has been writing and performing as long as he can remember. He attended Saint Louis University High (SLUH) college preparatory school but later dropped out of college to pursue a rock and roll career.

James Gunn is an American screenwriter, actor, producer, and director. He began to write and perform from an early age. When he was twelve years of age, he started creating 8mm films, most of which were comedic splatter films that featured his brothers being eviscerated by zombies. However, his professional career started as a screenwriter in the mid-90s.

After this, he started acting as a director with Slither, a horror-comedy film. Some of his notable works are Guardians of the Galaxy, Guardians of the Galaxy 2, and The Suicide Squad. He has also written and directed the superhero film Super. Apart from writing and directing these and many other films, he has executively produced I Am Groot, Avengers: Infinity War, and Avengers: Endgame.