We may be used to seeing guest stars on Glee, but we’re not quite used to seeing this.

Wednesday night in London, singer Leona Lewis welcomed a surprise guest onstage during her concert at O2 Arena: Matthew Morrison. The actor, who is currently in the area working on his solo CD, joined Lewis for a rendition of “Somewhere Over the Rainbow.”

Followers of the show know quite well this isn’t the first time Matthew has taken on the classic song. Gleeks recently saw Will Schuester perform it with Puck (Mark Salling) during the season finale. (In the event you missed that cover, you can watch it after the jump.)