What a sinister contraption that old oaken wardrobe is that has recently been put in Sveppi's brightly coloured children's room! He has inherited it from his grandfather, who was a magician by profession. The wardrobe, too, seems to have a few magic tricks to offer: At night it calls Sveppi by his name, and not only does this ominous piece of furniture swallow Sveppi's mobile phone, it also performs a vanishing trick with Sveppi's school friend Ilmus, who disappears without a trace. Together with his friends Villi and Gói, Sveppi seeks to disclose the wardrobe's secret. When the National Archives reveal that Sveppi's grandfather crafted it out of old planks from a ship that sank in 1725, the boys are one step closer to solving the riddle, but then a gang of crooks is on their trail, having set their sights on the valuable antique ... Sveppi's third cinema film proves to be yet another turbulent adventure. Once again all children's roles are embodied by adult actors. Iceland loves them for it.