Get a 1st look at 'The Office' star's behind-the-scenes photos from upcoming book

It's the cast of "The Office" like you've never seen them before — literally!

A new book about the hit NBC sitcom, "Welcome to Dunder Mifflin: The Ultimate Oral History of 'The Office,'" is set for publication in October, but we've got a first look at some of its never-before-seen photos right now.

Actor Brian Baumgartner, who played Kevin Malone on the Emmy-winning series, spent hundreds of hours interviewing his co-stars and the show's creators to piece together the story about how "The Office" came to be.

Included in the book are interviews with actors Steve Carell (Michael), John Krasinski (Jim), Jenna Fischer (Pam), Rainn Wilson (Dwight), Angela Kinsey (Angela), Craig Robinson (Darryl), Phyllis Smith (Phyllis), Kate Flannery (Meredith), Ed Helms (Andy), Oscar Nunez (Oscar), Amy Ryan (Holly), Ellie Kemper (Erin), Creed Bratton (Creed) and Paul Lieberstein (Toby).

Screenwriter and producers Greg Daniels and Mike Schur and producer Ben Silverman share their own memories of Dunder Mifflin and all its wacky employees.

Ricky Gervais, star of the British version of "The Office," on which the NBC series was based, also chimes in.

The photos that grace the book's pages have, until now, never been seen by fans.

One cute pic finds Krasinski, Fischer, Baumgartner, Helms and Carell posing together behind the scenes during filming of season four's "Fun Run" two-parter. Another snap shows Krasinski and Fischer shooting "The Fire" from season two.

One pic that will surely make fans feel emotional? A shot of the whole cast gathered together during the table read for the series' epic finale.

"Welcome to Dunder Mifflin: The Ultimate Oral History of 'The Office'" will be available on Oct. 19.

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