Ricky Gervais, Will Arnett to guest star in 'The Office' finale

NBC and producers of “The Office” are pulling out all the stops for the finale of this pivotal seventh season, lining up several major guest stars for the final episode.
EW can exclusively reveal that Ricky Gervais and Will Arnett will appear in the finale.
What will they be doing? Can’t say. The episode is still being written.
EW.com: ‘Office’ director on Steve Carrell’s final episode
We can tell you the one-hour episode will air May 19, have Gervais appearing on the show for the second time, and has Arnett appearing for the first time. Also, that there will be other notable guest stars as well.
Sources did warn that one shouldn’t assume that just because Gervais and Arnett are in the finale, that either is going to replace Carell next season as the “Office” boss (but one can dream of it, right?).
“The Office” is also returning after a few weeks of hiatus this Thursday with a major Michael Scott-centered episode titled “Garage Sale.” The set-up is that Dunder Mifflin will have a garage sale in the warehouse.

CNN.com