Rock of Ages has gotten used to a parade of lighter-flicking celebrity visitors at their hit musical comedy, but the last two of 2009 were a real treat: movie-musical alums Amanda Seyfried and onscreen/offscreen love Dominic Cooper of the blockbuster hit Mamma Mia!. The pair have first-hand experience with rocking familiar radio tunes the way the Rock of Ages entourage does (just rent their movie if you don’t believe us). Are Seyfried and Cooper eyeing an onscreen reunion in the adaptation of Rock of Ages, set to be released by New Line Cinema? (Seyfried would make a super-sweet Sherri…) Who knows. What we do know is you should take a minute to walk backstage with Rock of Ages‘ last VIPs of the decade.