Tom and Sophie Nightingale live on a barge with their zookeeper dad and vet mum, and as many animals as you can get on a small boat. Surely there's no room for any MORE animals in their life? But then there's a bat in peril, an owl on the prowl and an outbreak of night-terrors for the zoo's nocturnal residents. Tom and Sophie must stage a moonlit vigil to discover what's going on! An animal-packed caper written with the help of the brilliant team at London Zoo.