Katy Perry made her big X Factor comeback tonight!

The American songstress was a big part of last year’s series of the ITV show, standing in as a guest judge when Cheryl Cole was ill and performing her hit single Firework on the live shows.

Tonight she returned, this time to give a live rendition of her latest single “The One That Got Away”, taken from her third studio album, Teenage Dream.

Katy emerged on stage tonight, playing the guitar, which we totally didn’t know she could do. It was a very stripped back performance, in which Katy was joined onstage not by backing dancers, but by just two guitarists, a double bass player and a backing vocalist.

We also think she was singing live, which would make her the first to do so this evening, as both the final 12 contestants and The Wanted mimed their way through their earlier performances on the show.

The whole song had a bit of a country vibe about it and we just love how Perry can constantly reinvent herself and move from a shocking up beat track, to a fun party number, to an emotional and heartfelt ballad.

We think this has to be our favourite song that she’s released all year…it’s definitely one for the iPod!

Perry will also perform the song on November 20, 2011 at the American Music Awards.

How do you think Katy did tonight? Did you enjoy the performance? Leave your comments below.