Callum loves to build. And when he is given the most incredible construction kit for his birthday, his imagination runs riot! Callum takes his kit everywhere, and it comes in very handy. But as his constructions get bigger and bigger, the house begins to groan under the weight. Suddenly...CCRRRUUMMMFFFF!! the house crashes to the ground! Callum's construction skills are about to be put to the ultimate test!

Includes a large foldout.