Alytash and Leopold - Tash and Leo - are neighbours who used to be best friends, but aren't anymore, for reasons that Leo doesn't entirely understand. But now it's the last week of Year Six and Tash is standing in Leo's front yard with a misdelivered letter - and a favour to ask.

It's a request that will set off a chain of events in their little crescent in Noble Park, a suburb that is changing, and fast.

As they solve an unfolding neighbourhood mystery and help Ms Shepparson, a reclusive neighbour with a tragic past, Tash and Leo each has to confront fault lines in their own recent histories and families.

They will discover that friendships can grow and change, that bravery takes many forms, and that, most of all - whatever the future holds - friends and family are what matter.