The Naked Choir with Gareth Malone

Gareth Malone kicks off a singing contest with a difference, as he begins his search for the nation's most entertaining amateur group who can sing a cappella - without instruments or backing tracks, they must rely solely on their voices. In this episode, Gareth mentors the first four groups singing to stay in his contest. He'll strive to bring out the best performances from a London community choir, an Essex gospel group, six Southampton students and a group of female barbershoppers from Portsmouth, before they face a live audience and a jury of world-class a cappella experts. The jury's votes will decide which groups go through to the next stage and who will leave the contest for good.

Gareth Malone's exciting singing contest continues, as he searches for the nation's most entertaining amateur group who can perform a cappella - without instruments or backing tracks, they must rely solely on their voices. In this episode, Gareth mentors four new groups as they begin their battle to stay in his contest. Receiving Gareth's help and competing are a fledgling group of Salford students, a traditional male barbershop outfit from the Midlands, a gifted Glasgow University choir and an ambitious Birmingham six-piece, striving to bring a cappella to the masses. They will sing off in front of a live audience and a jury of world class a cappella experts. The jury's votes will decide which groups go through to the next stage and who will leave the contest for good.

Gareth Malone's continues his search for the nation's most entertaining amateur a cappella group - without instruments or backing tracks, they must rely solely on their voices. In this episode, Gareth brings the six surviving groups together for the first time, to contend with intensive mentoring at the state-of-the-art Performance Hub. The focus is on vocals. With the help of the best in the business, Gareth will tutor each group to improve their sound before they go head to head once more. They will compete in front of a live audience and a jury of a cappella experts - their votes decide who stays in the contest and which group will be heading home. Amid the gruelling training, two groups grapple with bringing emotion to their performances, while disaster strikes for another when an ill-judged high five takes an unexpected toll.

Gareth Malone's contest to find the nation's most entertaining amateur a cappella group continues - without instruments or backing tracks, they must rely solely on their voices. In this episode, the five groups left standing will be fighting for a place in the contest's semi-final. Gareth concludes his intensive training with more expert help and a new focus on performance technique. As the choirs strive to master choreography and stagecraft, one group aims to bring Big Top fun to their performance, while another struggles with sex appeal. Their training over, all five groups will compete once more, performing in front of a live audience and a jury of a cappella experts - their votes will decide who makes it through to the semi-final and which group will leave the contest for good.

It's the semi-final of Gareth Malone's contest to find the nation's most entertaining amateur a cappella group. To earn their place in the grand final, the four groups left standing must rise to a unique challenge - combine vocals, choreography and a killer concept to create a video with the potential to become an internet hit. Before the cameras even roll, one group has to contend with losing their leader, while a bizarre take on rapping threatens to derail another. Once in the can, the videos will be screened to a live audience and a jury of a cappella experts. Their votes will decide who goes through to the final and which group will leave the contest for good.