The evening at Lena's house looked ordinary - her mum was checking her little brother's lessons, her dad was on the phone and she was standing in the bathroom brushing her teeth. The day was full of excitement: a biology test, a quick game of basketball, delicious pizza with her friends. Lena was finishing brushing when suddenly a strange melody echoed in her head. She furrowed her brow and paused. Was it her thoughts playing tricks on her? Suddenly something began to glow in the mirror. Instead of a reflection, she saw a vast city, shimmering white and blue. Towers shaped like teeth, busy streets where they ran... toothbrushes and floss that seemed to have lives of their own! Lena wanted to blink and come back to reality, but before she could, the mirror sucked her in. She collapsed onto a soft cushion which, she quickly noticed, was one large molar. Conversations echoed around her. A strange creature ran up to her: a toothbrush wearing red glasses. - Hello, Lena! - he said, as if they had known each other for years. - There you are at last! The Queen of Toothbrush is waiting for you very much. - Excuse me? - Lena tried to look around, but the creature led her across a bridge made of dental floss, under which a river of mouthwash bubbled. - 'We've got a problem here that only you can deal with! - cried the brusque guide. - 'The Cuckoos have crept in here during the night...' It was the first time Lena had heard the word, but before she could ask, the bridge rocked dangerously. A shadow emerged from the depths of the river, and a mysterious murmur spread throughout Toothland. Lena felt the adrenaline begin to coursing through her veins. What awaited beyond the next bend in the bridge and why was she the only one who could help Tootholand...?