Oh, just Sir Elton John in the studio with Fall Out Boy's Patrick Stump.

Feel free to chalk this one under "Things We Thought Would Never Happen (But Are Still Glad They're Happening)." After announcing their unofficial reunion, complete with a brand-new song, "My Songs Know What You Did In the Dark (Light Em Up)" and an upcoming fifth studio album, Save Rock And Roll, Fall Out Boy are collaborating on a new song with a VERY unlikely artist: Elton John! (Also known as SIR Elton John in British circles.) Seriously, last thing we ever expected. But it's true: Elton is going to Save Rock And Roll with Fall Out Boy!

Read more about Fall Out Boy's collab with Elton John after the jump.

Snapped hanging out with the boys in an Atlanta studio, FOB guitarist Patrick Stump shared the photo on Twitter with the caption, "#sireltonjohn #saverockandroll." Though we're not sure yet which track Elton will guest on, we'd be lying if we said we weren't hoping to hear a little transition into "Crocodile Rock" or "Hold Me Closer Tiny Dancer" (also known as "Hold Me Close Young Tony Danza"). We also must express our deep excitement and support of this collab, not to mention our general anticipation for Save Rock And Roll -- we haven't heard any new FOB material since 2008 (five LONG years ago) and just knowing that a) the new album is but a month away and b) that Elton John will be on it is enough to make us bouncy-ball off the walls with glee! Till then, we'll  just make this image our desktop/iPhone/iPad background -- perfect staring material.

Look out for Fall Out Boy's Save Rock And Roll when it drops April 16, and catch them on tour starting May 14.

Photo credit: Patrick Stump