Gareth Malone presents the search for the nation's best amateur a cappella group. Gareth mentors the first four groups before they face a live audience and some a cappella experts.

Gareth Malone hosts the a cappella singing contest. Gareth mentors some Salford students, a Midlands barbershop outfit, a Glasgow University choir and a Birmingham six-piece.

Gareth Malone hosts the a cappella singing contest. Gareth brings the six surviving groups together for the first time, to contend with intensive mentoring at the Performance Hub.

Gareth Malone hosts the a cappella singing contest. Gareth concludes his intensive training with more expert help and a new focus on performance technique.

Gareth Malone hosts the a cappella singing contest. The groups must combine killer vocals and choreography to create a video with the potential to become an internet hit.

Gareth Malone presents the final of the search for the nation's best amateur a cappella group. There is one more performance to go, but their last challenge has a fiendish twist.