How many movies have James T. Walker and William Hanna collaborated on?

They have worked on 4 movies together! Their first movie together was Scooby-Doo! Meets the Boo Brothers (1987) while their highest rated movie together was Scooby-Doo on Zombie Island (1998). They have not worked together since Tom and Jerry: The Magic Ring (2002). They are most known for their family films together.