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. Show less