Sitting at the intersection of two main arteries of traffic on Melbournes Northside is a giant yellow rat that is pointing, with a long gnarled claw, to its explicitly large bottom. This yellow rat is the mascot for the small business Glenlyon Motors. This unusual mascot and the absence of an explanation for its existence has many residents of Melbournes north side puzzled. 'A Rats Arse' finally answers the question on every Northside residents lips - “Why?!” - and along the way reveals something about identity, values, community, and the people who exist within them.