The teams have to build a funfair with at least one spectacular supersized mechanical ride. And they have to build a vehicle out of the blue. Richard Osman guest judges.

It's the final stage of the contest and the brick builds include a robot with an ostrich head and an alien from the planet Zorg. Guest judge is comedian Dara Ó Briain.

The teams compete to build a hybrid land and sea animal and a life-size crazy golf feature. Comedian Chris Ramsey tees off as this episode's celebrity guest judge.

The four teams build a walking-talking robo-pet. There is also a Master Build using as many as half a million bricks. But who will be crowned the winner for 2018? With guest judge Sue Perkins.

The remaining teams head for the great outdoors, competing to build the best brick display in an Essex wood. There's even a Madagascan crocodile. Guest judge is comedian Bill Bailey.

The teams compete to construct a skyscraper and a metre-long bridge that will withstand a weighted dumper truck . This episode's guest is comedian Rob Beckett.

The seven teams do battle in a drop test to see which model gets smashed up the best. They also build a memorable scene from history. Joining the judges is comedian Paddy McGuinness.

The eight teams compete to create a spectacular brick banquet and at least one supersized masterpiece for the banquet table, including duck and prawn toast, hog roast and a gravity defying cuppa

It's the semi-final. The teams create a bust of comedian Johnny Vegas. Can they capture the essence of Johnny in plastic bricks? They also build a life-size arcade game.