He'll join the veteran NBC comedy as a series regular as the series reboots itself for Season 9.

Dunder Mifflin has added a new office mate.

Better With You's Jake Lacy has joined NBC's The Office, The Hollywood Reporter has confirmed.

As first reported by TV Line, Lacy will be a series regular on the veteran comedy's upcoming ninth season as the series continues its reboot for Season 9.

For Lacy, the casting comes not long after he was dropped from Fox's midseason comedy The Goodwin Games, where he co-starred in the pilot alongside Becki Newton and Scott Foley.

Lacy joins new co-star Clark Duke (Greek), who also joins The Office as a series regular as the series -- NBC's top comedy -- looks to rejuvinate itself amid a revolving door both in front and behind the camera.

Co-star Mindy Kaling confirmed she will return to the series as Kelly Kapoor for a handful of episodes while juggling writing and acting duties on her freshman Fox comedy The Mindy Project.

B.J. Novak also will not return as a series regular, reducing his role to recurring and continuing to write and direct episodes of the series. (Novak was an executive producer on Mindy and will contribute to her Fox comedy though he does not have a permanent position on the series.)

Meanwhile, stars Ed Helms, John Krasinski and Jenna Fisher, are all poised to return to the comedy, with Season 8 recurring guest star Catherine Tate upped to series regular in June.

The Office has seen a somewhat revolving door since star Steve Carell's departure last year. In addition to the cast moves, showrunner Paul Lieberstein stepped down to focus on a potential Rainn Wilson-centered Dwight spinoff, with Greg Daniels returning to helm the series, which was renewed in May after the cast finalized deals to return.

The series also added two new executive producers -- Dan Sterling and Brent Forrester -- to help fill the void left by Lieberstein's departure.

Lacy is repped by ICM Partners and Beth Rosner Management.

The Office returns Thursday, Sept. 20 at 9:30 p.m. on NBC.

Email: Lesley.Goldberg@thr.com; Twitter: @Snoodit