How many movies have Reverend W. Awdry and Robert Hartshorne collaborated on?

They have worked on 7 movies together! Their first movie together was Thomas & Friends: The Great Discovery - The Movie (2008) while their highest rated movie together was Thomas & Friends: Hero of the Rails - The Movie (2009). They have not worked together since Thomas & Friends: Sodor's Legend of the Lost Treasure: The Movie (2015). They are most known for their family films together.