And despite packing out the south London venue with screaming fans, Cheryl Cole's biggest supporters were clearly her BFFs as they tweeting their excitement and pride at her performance.
Nicola Roberts got emosh as she watched Cheryl wow on her 'A Million Lights Tour' tweeting: "I am so so so so proud right now.. wiping tears @CherylCole #AMillionLightsTour"
While Strictly Come Dancing star Kimberley Walsh posted: "so unbelievably proud of @Cherylcole right now!!!!!!!!! Love her tooooooo much! #amillionlights".
Kimberley, Nadine and Nicola were spotted sitting together at the O2 and Cheryl's PR company posted this picture of the three of them together. But there was no sign of fifth member Sarah Harding.
Later ginger beauty Nicola posted a pic of herself, Kimberley and Cheryl Cole after the gig with lots of hearts.
And with Chezza's other BFF will.i.am making a surprise appearance on stage, Nicola got excited and starting snapping pictures of the two of them - including will's glow in the dark outfit.
Earlier in the day Kimberley could barely contain her excitement at seeing her bestie on stage posting: "I am beyond excited to see @CherylCole at the 02 tonight!!!!!!!!!!! Cannot WAIT! #chezzaontour #amillionlights arrrggghhh!!!"
She added: "The wait is over the wait is over" #amillionlights"
Cheryl took to Twitter to express her excitement after the gig, posting: "LONDON THE ROOF WAS ON FIRE !!!!!!!!!!! #ProudSoldier"