From the dynamic, dream team of Jon Klassen and Mac Barnett comes the final instalment in the hilarious shape trilogy. `Simple shapes and succinct story express big ideas. Makes us consider fear of strangers, the power of the imagination, being brave and standing by friends` -Sunday Times Triangle and Square are visiting Circle, who lives at the waterfall. When they play hide-and-seek, Circle tells the friends the one rule: not to go behind the falling water. But after she closes her eyes to count to ten, of course that`s exactly where Triangle goes. Will Circle find Triangle? And what OTHER shapes might be lurking back there?