Filming for "Grey's Anatomy" season 13 has officially begun with the cast and crew revelling in their reunion on social media.

Actress Debbie Allen, who plays the role of Catherine in the series, tweeted about the first day of filming saying "Nothing beat the smell of a re-opened set!"

Show creator Shonda Rhimes also took to Twitter to commemorate the beginning of the "Grey's Anatomy" season 13 filming and to share her appreciation for her work at the show.

"Today we begin shooting the 270th episode. And I remember wondering if we'd get to shoot 13," Rhimes, adding a hashtag about how she loves her job.

Producer Karin Gleason also shared a bunch of teases about the return of the cast and crew on set for the highly-anticipated new season of "Grey's Anatomy."

She shared a photo of the entrance doors of the Grey Sloan Memorial Hospital. She also posted another snap, this time featuring a cake that was part of the first day of filming celebration.

In another tweet, she detailed their progress. "And... we're off! First scene in the can. Cast [and] crew bringing it. 'Grey's Anatomy' season 13 has begun!

Before the production began, the "Grey's Anatomy" squad already reunited with a kickoff party last Saturday, July 30 where Allen, Rhimes and Ellen Pompeo, who plays Meredith, danced their heart out.

As far as details on the "Grey's Anatomy" season 13 plot go things are still being kept a secret. However, fans can expect to see conflict arise among Meredith, Maggie (Kelly McCreary) and Riggs (Martin Henderson).

Fans will also get to check back in on newlyweds Owen (Kevin McKidd) and Amelia (Caterina Scorsone). "Grey's Anatomy" season 13 will also see Alex (Justin Chambers) learn the truth why Jo (Camilla Luddington) just can't marry him, at least not yet.

"Grey's Anatomy" season 13 premieres Thursday, Sept. 22 at 8 p.m. ET on ABC.