London-based three piece Lovable Rogues and 11-year-old Molly received the most votes during the third semi-final.
They have joined pop-opera duo Jonathan and Charlotte, Latin American ballroom dancers Kai and Natalia, Pudsey the dancing dog with partner Ashleigh and Welsh male choir Only Boys Aloud in Saturday's final.
The Lovable Rogues stormed through to the final, winning the public vote. The boyband could not hide their delight after confirming their place in this weekend's competition showpiece.
"It feels incredible and we had the best response from the public who voted. It's now sinking in a little bit and the adrenaline is starting to slow down. We've been very busy and that's what we want."
Judge Simon Cowell also praised the trio and labelled their performance as "brilliant" on the night.
For Molly, who performed her own soulful rendition of Roxette's "It Must Have Been Love", she went through as the public's second favourite act after the judges failed to make a decision and left the choice up to the public poll.
Molly, from Essex, received glowing tributes from judge David Walliams - who likened her voice to that of an adults.
She said: "It's amazing and words cannot describe how I feel now. I'm so excited for the final and to have the support of the public is amazing."