Written by Stacy McKee and directed by Kevin McKidd, the episode aired on the American Broadcasting Company (ABC) in the United States on September 24, 2015.

Other storylines include Miranda Bailey (Chandra Wilson) vying for the position of Chief of Surgery with the support of Richard Webber (James Pickens Jr.), and Arizona Robbins (Jessica Capshaw) searching for a new roommate after her split from Callie Torres (Sara Ramirez).

Additionally, relationship tensions rise for couples Alex Karev (Justin Chambers) and Jo Wilson (Camilla Luddington), as well as Jackson Avery (Jesse Williams) and April Kepner (Sarah Drew).

The episode opens with a voice-over narration from Meredith Grey (Ellen Pompeo) about letting go of the past and embracing a fresh perspective on the familiar.

Meredith Grey (Ellen Pompeo) moves back into her old home and must adjust to living with her half-sister Maggie Pierce (Kelly McCreary) and sister-in-law Amelia Shepherd (Caterina Scorsone).

After learning from Stephanie Edwards (Jerrika Hinton) why no one wants to live with her, she reluctantly agrees to take in intern Andrew DeLuca (Giacomo Gianniotti) as her roommate.

April Kepner (Sarah Drew) returns from a three-month deployment in Jordan, but her reunion with her husband, Jackson Avery (Jesse Williams), is cold and distant.

The twelfth-season premiere of Grey's Anatomy marked the first episode not feature Patrick Dempsey as a series regular post his departure in Season 11.

The American Broadcasting Company (ABC) also reimagined the series without its iconic character, "Derek "McDreamy" Shepherd", with the network's president expressing hope that the show could continue for many more years after Dempsey's departure.

"[1][2] It was also revealed that Joey Lauren Adams would guest star in the upcoming season, competing with Miranda Bailey (Chandra Wilson) for the role of Chief of Surgery.

Additionally, Eric Lange, Maz Jobrani and Jenny Cooper co-starred in a patient storyline involving two young girls who attempt suicide.

[5] "Sledgehammer" received positive reviews from television critics upon telecast, with many praising the show's return to form and noting that it recaptured the tone and style of the earlier seasons.

[9] Zap2it also highlighted the emotional power of the love story between the two young girls, while TVOM praised Pompeo's character, remarking, "The show's titular heroine had to learn to move forward with her life, and based on the season premiere, we would be wise to stick around for the journey."