Episode 4

All Together Now, hosted by comedian Rob Beckett, is back with more memorable performances, including two brothers singing their hearts out with a Morecambe and Wise classic, and a charity worker with a jaw-dropping performance of Labrinth's Jealous.

In this fourth episode, a mix of talented singers take to the stage to perform in front of the 100 - a panel of music experts and performers from all over the UK. If any of the 100 like what they hear, they can stand up, join in and sing along. The greater the number that join in, the higher the act's score.

Heading up the 100 is Spice Girl Geri Horner. As a member of the best-selling girl group of all time, Geri knows exactly what it takes to get a crowd joining in and singing along.

The hopefuls this week perform a range of singalong classics, including recent hits such as Pharrell Williams's Happy. There are two iconic songs from two popular movies - Climb Every Mountain from The Sound of Music, and Skyfall, the title theme from the James Bond film of the same name. We also head back to the 70s with Candi Staton's Young Hearts Run Free and The Jackson 5 hit Who's Loving You .

The acts, a mix of professionals and amateurs, take to the stage in the hope of winning over the 100 and making it into the top three. The winner is guaranteed a place in the final, with the acts in second and third place each performing another great song in a dramatic sing-off. The winner of the sing-off also goes through to the final.

There really is something for everyone, with lots of laughs from Rob and the 100. By the end of tonight's show two more acts will reach the grand final, where one of the finalists will win £50,000.