One of the more interesting tours of the summer is the "Rock Paper Scissors" tour featuring Sting and Peter Gabriel. The two veteran musicians are performing with both of their bands onstage at the same time, trading off songs, backing each other up and occasionally covering each other's material. But as interesting as that sounds, fans in Seattle got an extra bonus when Pearl Jam's Eddie Vedder chimed in on the fun.

While performing at Key Arena Thursday night (April 21), the veteran musicians surprised the crowd with the addition of Vedder, who walked on during Sting's performance of "Driven to Tears" and traded vocals with The Police frontman throughout the track. Greeted warmly by the Seattle audience, Vedder and Sting punctuated the track with a leap in the air to finish the song. You can watch fan-shot video of the performance above.

But Vedder wasn't done. Having joined Sting onstage, after a performance of "Fragile," Vedder returned to play with Peter Gabriel. This time the song of choice was Gabriel's "Red Rain," which found Vedder at center stage, while Gabriel sat off to the side at his piano, singing and playing through the track. As the song concluded, Vedder walked toward the piano, greeted Gabriel and walked off as Gabriel simply pointed out that it was "Eddie." Fan shot footage of Vedder with Gabriel can be seen below.

Vedder has a handful of August dates with Pearl Jam on the books (see those here), and will also headline night one of the Ohana Festival in Dana Point, Calif. on Aug. 27.

Watch Eddie Vedder Perform "Red Rain" With Peter Gabriel

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