Ten shy children who love to sing but are terrified of performing in public are put through their paces by choirmaster extraordinaire Gareth Malone. Having already worked his magic on a tone-deaf town, reluctant schoolboys and wayward teenagers, Gareth attempts to build the youngsters' fragile confidence and turn them into singing stars capable of performing in front of a massive crowd - 40,000 people at London's Proms in the Park. Twelve weeks ago, Gareth scoured the country for shy singers in need of a confidence boost and found Annabel, Isthaque, Jordan, Katie, Oli, Miriyah, Emily, Howard, Chloe and Chris. Each week the Big Performance tour bus stopped at different locations, and the group faced new performance challenges. Whether singing in front of each other, to Gareth's old school choir, or to a crowd of 15,000 people at Reading Football Stadium, they were terrified. As Proms in the Park got closer, the audiences grew bigger as each singer tried out for the coveted solo spot. Each week they tackled a different musical style - pop, rock, classical and country didn't all go down well. After eleven weeks of gruelling training, the soloist is picked, there is no going back. 40,000 people wait to see if Gareth's group can hold their nerve and deliver the performance of a lifetime.