Barry wrote or rewrote screenplays for several notable films including The River starring Mel Gibson and Sissy Spacek, Eyes of Laura Mars starring Faye Dunaway and Tommy Lee Jones, and Rhinoceros, starring Zero Mostel and Gene Wilder, Me, Myself and I, starring George Segal and Jobeth Williams, and the American Playhouse production for PBS, A Marriage - Georgia O'Keeffe and Alfred Stieglitz, starring Christopher Plummer and Jane Alexander. He also appeared as himself in the film documentary Pablo, about the graphic artist and film director Pablo Ferro.
His autobiography My Night With Orson was published in 2011.
Barry was born in 1930 and raised in Riverdale, the North Bronx. He played saxophone for his high school band, and traveled to jazz clubs in New York City to hear jazz performed by Charlie Parker, Dizzy Gillespie, Miles Davis, Thelonious Monk and John Coltrane.
After high school, Barry attended Syracuse University in Syracuse, New York, where he majored in drama and performed in university productions with comedian Jerry Stiller. He was drafted into the Army during the Korean War and served until 1953.
Barry was cast in the 1955 Orson Welles production of King Lear at New York City Center theater. He continued working on Broadway as an actor in the musical Shinbone Alley, where he was also stage manager, He also stage managed the Budd Schulberg treatment of The Disenchanted, about the real life adventures of F. Scott Fitzgerald. He stage managed seven other Broadway productions, appearing as an actor in several of them as well, and he worked in the Broadway theatre in this capacity through the mid sixties when he started writing full-time.
In 1969, Barry was hired by Columbia Pictures to write the screenplay for Lenny. The prospects for the project were reportedly harmed by the commercial success of Love Story, having created a demand for romantic films, which Lenny certainly was not. Barry suggested to theatre director Tom O'Horgan, who was fresh from his success with the musical Hair, that the Lenny screenplay be redone as a play and the play was a hit starring Cliff Gorman.