Idina Menzel

OMG, it's Princess Elsa! The Tony Award-winning star of 'Wicked' and TV's 'Glee' had her profile further raised last year when her voice starred in Disney's 'Frozen', and the film's epic ballad 'Let It Go' catapulted her into the enormodome league. Thus she's now comfortably able to fill up Wembley Arena to belt out show tunes and her own material. She's just released a Christmas album, too, but showcasing numbers from that record might sound a little off-topic by the time this show rolls around in June.