The veteran builders have 12 hours to construct a section each of a great ball contraption, through which a ball must pass seamlessly from one team's table to the next. Just don't drop the ball!
Series 7 Episode 1
Bringing the World Together: Who'll drop the ball in the very first challenge - the notorious great ball contraption?
Series 7 Episode 2
Birdman: Will pigs (and dragons and chickens) fly when the teams create incredible Lego gliders?
Series 7 Episode 3
What's in Toy Store: It’s all to play for as each duo picks an empty toy package and must invent a matching toy
Series 7 Episode 4
Is It Fake?: It's about to get real (and fake), as the teams recreate items from a Chinese restaurant
Series 7 Episode 5
What Lurks Beneath: History above meets mystery below, in a tricky dual design with a watery surprise...
Series 7 Episode 6
Run the Gauntlet: Boom! Crash! Bang! Whose booby traps will stop Hamish Blake's Lego car in its tracks?
Series 7 Episode 7
Caught in the Act: Which team can pull off the perfect crime scene? Can detective Sophie Monk crack the case?
Series 7 Episode 8
Fresh Food People: From Captain Corn to Banana Boy, our 'pears' pit juicy new heroes against rotten villains
Series 7 Episode 9
Movie Magic: The five remaining teams create Hollywood-worthy car scenes, in the race to the semi-final
Series 7 Episode 10
Harry Potter: In a spellbinding semi-final, the top four teams face a magical Harry Potter challenge