Join mParticles first annual Charity Challenge and uncover the Secrets of the Squares. This is a cryptic Treasure Hunt through Central London where solving each clue correctly leads to another -  treat it as a race or take your time , either way enjoy the sights and sounds of a variety of hidden secrets - just make sure you get to the end point to avail of our hospitality and raise some much needed funds for those in Ukraine who need it most.