Rihanna joined Calvin Harris onstage last night at Coachella.
Speculation was 'rife' ('everyone figured it out immediately') that something was going to happen after Harris tweeted: "There might be an exciting surprise during my Coachella set later !"
With 'Worst Day' collaborator Izza Kizza nowhere near the festival it was assumed that Rihanna, who had been tweeting pictures from the site since Friday, might be up for a bit of a sing song and so it came to be.
According to the Hollywood Reporter the pair performed her forthcoming single 'Where Have You Been' and minor hit 'We Found Love'.
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