- Illustrator: Marja-Liisa Plats
- 2016, 152 pp
- ISBN: 9789949986804
- Age: 9+
- fiction, storybook
The Jõmmu, a huge old-fashioned riverboat, has disappeared! Police are baffled – nothing suspicious has been seen either upstream or downstream. The curious kids of the Secret Souptown Society – Mari, Satu, Reelika, Olavi, and Anton – have to figure the case out, cost whatever it may. Timo, a boat enthusiast, joins their group and is a huge help to his friends. Nevertheless, the kids get into increasingly complicated and sometimes downright dangerous situations while solving the mystery. There’s no answer in sight, but the Jõmmu must be somewhere!
The first book in Keränen’s The Souptown Secret Society series was The Stolen Orange Bicycle (2008). The Good Ship Jõmmu is the eigth.