It happened at The County Theater in Doylestown on July 2nd.
Authorities say the man tried to sneak a small dog into the theater but the manager told him he couldn't take the dog inside.
The man got angry, punched a theater volunteer in the face and fled.
Police released a composite sketch of the man on Thursday.
He is described as a white man in his mid-50s, between 5'11" and 6'2" tall with gray hair and a pony tail.
Anyone with information is asked to call Doylestown police at 215-345-4143.
