The Snork has made a new invention; a super-glue that sticks to everything and won't come off easily, either. While his sister Snorkmaiden is out with Moomin and the others trying their luck at fishing, the Snork cooks glue in Snorkmaiden's kitchen, making rather a mess of the place. On her return Snorkmaiden is truly miffed and moves into Moominhouse, leaving the snork to fend himself. Getting brother and sister together again seems no easy task, but the fish party Moomin is throwing to celebrate (and eat) his record catch seems to offer possibilities...