1980 AD. In Yorkshire, the authorities have dismissed reports that an Unidentified Flying Object was seen plummeting towards the ground... moments before the explosion that destroyed the Blackcastle Steel Mills. After all, Blackcastle is the last place on Earth aliens would ever want to visit... Local teenagers Sharon and Fudge know better. 'Cos they've found an actual space alien hiding in the allotments. He's their alien. Their secret. And his name is... The Meep. He's not the only alien in Blackcastle, though. His pursuers, the terrible Wrarth Warriors, are on his trail, along with their unwitting accomplice: The Doctor.
—Big Finish Productions