U2 invited Patti Smith out onstage at the O2 Arena in London last night (October 29th).
The Irish group are mid-way through a flurry of shows at the enormous venue, and previously brought out Noel Gallagher for a quick cameo role.
Easing themselves into 'Gloria', Patti Smith then appeared to jolt U2 into life. The punk-poet stayed onstage for a version of her classic anthem 'People Have The Power'.
Check out some fan footage below.