Giant Lego advent calendar built in Covent Garden market
23 December 2012 Last updated at 11:12 GMT
Duncan Titmarsh is the only man in the UK that can call himself a 'Lego Certified Professional. And here's why!
He leads a team of people that build special sculptures out of Lego, and this year has been asked to build an advent calender.
It's been built for the Christmas market in London's Covent Garden.
The team have used over 600,000 bricks in the process!
Find out how it was done right here!