Keaton to Play Kline's Wife in Kasdan's ‘Darling Companion’

Oscar nominee Richard Jenkins and Emmy nominee Elisabeth Moss have also joined the indie dramedy's cast

Diane Keaton is in final negotiations to join Kevin Kline, Richard Jenkins and Elisabeth Moss in Lawrence Kasdan's indie dramedy "Darling Companion," the Oscar-winning actress' representation at WME has confirmed to TheWrap.

Keaton and Kline will play a married couple who take in a stray dog. She loves the dog more than her often-distracted husband, and he winds up losing the pooch after a wedding at their vacation home in the Rockies. Uh oh! Looks like someone's sleeping on the couch! Several wedding guests set out to search for the animal, including a mysterious young woman.

Just imagine Kelly Reichardt's "Wendy and Lucy" if Michelle Williams' character had been married, and that should give you an idea as to what Kasdan has up his Oscar-nominated sleeve.

Kasdan wrote the script with his wife, Meg Kasdan, who will exec produce with Christine Walker and John Kelly. Lawrence Kasdan will produce with Likely Story's Anthony Bregman and Elizabeth Redleaf of Werc Werk Works.

The Hollywood Reporter notes that the project "is meant as the third in a trilogy" that includes Kasdan’s “The Big Chill” and “Grand Canyon,” the latter of which which he also wrote with Meg.

"Darling Companion" is scheduled to begin production later this month in Utah.

Keaton next stars opposite Harrison Ford and Rachel McAdams in Roger Michell's "Morning Glory," which Paramount will release on Nov. 12. She has been filming HBO's "Tilda," in which she plays a ruthless Hollywood blogger modeled after Deadline editor-in-chief Nikki Finke.

Jenkins has been in serious demand since earning an Oscar nomination for his performance in 2007's "The Visitor." He recently starred opposite Julia Roberts in "Eat Pray Love," and will soon be seen in two genre films — Matt Reeves' "Let Me In" and Drew Goddard's "Cabin in the Woods." Coincidentally, Reeves and Goddard respectively directed and wrote "Cloverfield."

Additionally, Jenkins will reunite with the Farrelly Bros. (he played Ben Stiller's absentee shrink in "There's Something About Mary") for their upcoming comedy "Hall Pass," and is set to appear in Will Gluck's comedy "Friends With Benefits" and Bruce Robinson's "The Rum Diary."

Jenkins also co-stars in Josh Radnor's "Happythankyoumoreplease," which Deal Central hears may be released in February.

Moss is best known as the Emmy-nominated actress who plays Peggy Olson on AMC's "Mad Men." She recently starred opposite Jonah Hill in "Get Him to the Greek," and just wrapped the indie "Buddy Gilbert Comes Alive." Moss is currently filming Walter Salles' adaptation of "On the Road."

Kline recently starred opposite Paul Dano in "The Extra Man," and he co-stars in Robert Redford's period legal drama "The Conspirator." The Oscar-winning actor recently wrapped Ivan Reitman's romantic comedy "No Strings," which oddly enough had to change its original title of "Friends With Benefits" because of Gluck's film.

As for Kasdan, he hasn't stepped behind the camera since 2003's "Dreamcatcher," which was one Stephen King adaptation not worth catching. He previously directed Kline in "The Big Chill," "Grand Canyon," "Silverado" and "French Kiss."

Kasdan and Kline are represented by CAA, while WME represents Moss and Gersh reps Jenkins.

Production Weekly first reported the casting of Keaton and Jenkins on Twitter, while Deadline chimed in with the Moss news.