Benedict Cumberbatch led calls for an encore at The Killers' iTunes Festival gig.
The Sherlock actor was spotted among the crowds at London's Roundhouse, where he rocked out to the band's greatest hits.
Brandon Flowers and the band thrilled crowds with slick versions of songs including Jenny, Human and Mr Brightside, and some new material including the Pet Shop Boys-esque Flesh And Bone.
When they left the stage, Parade's End star Benedict was among the first to shout for an encore.
The actor stamped his feet and clapped in time, to cries of "Elementary!" from fans who had spotted him.
The Killers release their first album in two years, Battle Born, on Monday and are streaming it this week on iTunes.
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