Jesse Williams returned to Grey’s Anatomy in Season 22, Episode 4, as Dr. Jackson Avery, marking his first appearance since the Season 21 premiere. The episode aired Thursday, October 30, 2025, and featured a clash between Jackson and Meredith Grey over flawed Alzheimer’s research methodology. Their conflict escalates during a dual surgery, ultimately leading to Jackson’s apology and Meredith’s decision to relocate to Boston for full-time laboratory research. The episode also advanced multiple character storylines involving interns, residents, and established physicians navigating personal and professional challenges.[1][2][3][4][5][6]
Episode Details and Jackson’s Return
Grey’s Anatomy Season 22, Episode 4, titled “Goodbye Horses,” aired Thursday, October 30, 2025, at 10 p.m. ET on ABC. Jesse Williams reprised his role as Dr. Jackson Avery in his fourth guest appearance since departing as series regular in Season 17. This marked his first appearance since the Season 21 premiere.[2][3][4][5][7][1]
Alzheimer’s Research Conflict Between Jackson and Meredith
Meredith Grey identifies flaws in published Alzheimer’s study methodology. The dispute centers on research conducted by Dr. Tom Koracick, a former Grey Sloan Memorial surgeon played by Greg Germann. Koracick published findings based exclusively on male mice. Meredith replicated the experiment using female mice and obtained contradictory results.[3][4][2]
Jackson initially dismisses Meredith’s concerns, citing her empty laboratory and absent publication record. The tension escalates during their collaborative surgery when Jackson remarks sarcastically about her inability to publish findings.[4][2]
| Study Element | Koracick (Male Mice) | Meredith (Female Mice) |
|---|---|---|
| Subject population | Male only | Female only |
| Results | Positive Alzheimer’s reduction | No disease reduction |
| Publication status | Published | Unpublished research |
Dual Surgery Transforms Professional Dynamics
A cancer survivor requires both breast reconstruction and hernia repair surgery. Jackson initially opposes performing both procedures simultaneously, citing surgical protocol. Meredith recognizes the patient’s deeper need—reclaiming identity beyond cancer survivor status—and commits to the combined operation.[5][2][4]
Jackson makes disparaging comments during surgery, but witnessing the patient’s gratitude afterward prompts genuine apology. He subsequently offers Meredith a ride to Boston, which she accepts.[2][4]
Meredith’s Boston Laboratory Research Transition
Meredith relocates to Boston for full-time Alzheimer’s research work. Chief Resident Richard Webber anticipated this departure, immediately reassigning her surgeries after reviewing Koracick’s report.[4][5][2]
Showrunner Meg Marinis confirmed Meredith will divide time between Boston and Seattle, targeting increased Seattle appearances. Marinis stated: “The more we get Ellen, the happier I am”.[5][2]
Key Supporting Character Developments
Multiple storylines advanced throughout the episode:
- Lucas requested to remain on patient Katie’s care team after helping her find clinical trial options[2][5]
- Bailey encouraged Ben to pursue three additional plastic surgery residency years[5][2]
- Jules declined roommate arrangement with Simone to preserve friendship[4][2]
- Kwan feigned food poisoning to allow Kavita surgical opportunity with Jackson[2][5]
- Owen apologized to Link for lashing out about patient involvement before return-to-work approval[6][4]
- Owen invited resident Nora to dinner after learning about her breakup with Teddy[8][6][4]
- Teddy explained seeking control through intimate moments with Cass Beckman[9][6]
- Cass proposed public partnership to strengthen Teddy’s sense of agency[6][9]
Owen and Teddy are separated, not finalized divorced. Sources describe their status as “breakup” across TVLine, TV Insider, and Deadline.[10][11][8]
