Gareth Malone visits Lewisham healthcare NHS Trust to set up the first choir

In his mission to get some of the country's busiest workplaces singing, Gareth Malone heads west to the Royal Mail in Bristol. He wants to create the second of four choirs that will compete in the contest to find his best workplace choir. As he searches for hidden talent amongst the managers and posties from across the region, the initial reaction from staff is quite mixed. But as the choir begin to bond through rehearsals, Gareth discovers an enormous sense of pride in the workforce and the song he chooses for the choir to sing hits the right note.

With two choirs established, Gareth heads north to recruit baggage handlers, air traffic control workers and firemen at Manchester Airport.

Choirmaster Gareth Malone continues his mission to get some of Britain's busiest workplaces singing. This week he travels to the Midlands to set up final choir in one of the country's largest water companies, Severn Trent Water. Once formed, the choir will sing against three other workplace choirs as they compete for the chance to be crowned Gareth's Best Workplace choir. With over five thousand call centre staff and over five hundred workmen, dealing with everything from raw sewage and finding leaks, finding thirty people to make up the choir appears easy. But as staff are struggling to juggle family commitments and busy work schedules, things aren't plain sailing and Gareth begins to feel the pressure.

With all of his workplace choirs set up, the contest to find Gareth Malone's best workplace choir begins in earnest as all four choirs compete against each other for the first time. Each choir is given a new song and Gareth piles on the pressure by announcing that they must create a distinctive performance routine if they want to stand out. Each choir has less than four weeks to prepare, before they must perform in front of the three expert judges at Bristol's prestigious Colston Hall. Only three choirs will make it through to the final, one choir will leave but which will it be: Lewisham NHS Trust, The Royal Mail, Manchester Airport or Severn Trent Water?

After last show's semi-final performances in front of the judges, it is time for the final three to battle it out. They face their biggest challenge yet as they perform in front of an audience of thousands at one of the world's most prestigious choral music festivals - the International Eisteddfod in Llangollen. In the audience will be the three expert judges who will decide which choir will win the overall contest and be crowned Gareth's Best Workplace Choir.