This week, Gareth is on home turf as he scours the south west of England for a third regional champion to put through to his nationwide contest. Pit stops include hay barns, harbours and a high tea, on an audition tour that features a Bristol sea shanty band, a cake-loving WI group, a Guernsey church choir and some tuneful young farmers from Devon.

To top it all, Gareth umpires a Pitch Perfect-style song battle between Exeter University's two top a cappella acts. But who from among these hopefuls will Gareth select for the sing-off? Success at this sing-off will secure a place in the national stages of the competition, but also comes with a challenge - ahead of the national contest, the winning choir must work with Gareth to pull off a performance in their home town.

Gareth Malone aims to find Britain's most entertaining amateur choir. It is the semi-final of Gareth Malone's contest to find Britain's most entertaining, undiscovered amateur choir. The four groups Gareth has handpicked from across the country are being brought together for the first time at bootcamp, before they go head to head to stay in the contest. They face intensive mentoring as part of a challenge designed to target and overcome their musical weaknesses. Two choirs grapple with picking the perfect soloist, while another must tackle their lack of self-belief. It is a race against the clock to perfect their semi-final performances before the groups sing live in front of an invited audience and a jury of musical experts. The jury's votes decide which groups will go through to the grand final and which choir will leave the contest for good.