As fog begins to cover Seattle, the doctors of Grey Sloan navigate through personal complications. Meredith and Alex attempt to save Gus, while Levi talks some sense into a struggling Nico.

Alex tries desperately to save his patient Gus while he waits for a severely agoraphobic blood donor to arrive from London. Jo reveals to Meredith why she's been so down, while Catherine and Bailey hold a meeting to get down to the bottom of an insurance issue. Meanwhile, Maggie and Jackson go camping.

Maggie treats someone from Station 19; Jo learns a hard lesson; when working with a family that is seeking asylum, Meredith makes a call that could jeopardize her career.

Meredith debates how to handle an unexpected situation in her personal life, while Richard has an untimely reunion with an old friend. Jo has a hard time at work, and Owen tries therapy.

Amelia and Link travel to New York to operate on a patient with a severe spinal deformity, but they're in for more than they bargained for when Nancy Shepherd invites them to dinner at her home.

Owen and Teddy have to deal with the surprise arrival of Megan Hunt, who knows nothing about their situation. Catherine preps for her first surgery back on a war veteran who's not emotionally prepared for his procedure. Meredith worries about DeLuca operating alone with Richard.

When a trauma patient arrives at Grey Sloan, it forces Jo to confront her past. Meanwhile, Bailey and Ben have to talk to Tuck about dating.

Maggie introduces mood rooms as an alternative approach to medicine. Alex and DeLuca butt heads over an 11-year-old patient who tries to sabotage her own surgery. Jackson and Richard deal with a gender non-binary patient. Meanwhile, Teddy has a pregnancy scare that brings Owen and Koracick to odds.

Ties are strained as Andrew and Carina confront an unforgiving family history. Meanwhile, Teddy and Owen work together on a married couple who is expecting, and Amelia attends a conference for alternative pain relief.

Meredith finds herself having to side with either Alex or DeLuca during a difficult situation, but she doesn't want to betray either of them. Meanwhile, Maggie reveals details about her personal life that cause a public stir, and Levi struggles with whether or not to tell his family about Nico.

When Jackson throws a party to celebrate Catherine's surgery and those who worked to save her, literally nothing goes as planned. Meanwhile, Helen pays Alex and Jo a surprise visit.

While Meredith breaks a hospital record, the rest of the doctors are sent scrambling in the wake of a massive overdose within the community. Meanwhile, Jackson wants to take a reluctant Maggie camping, and Levi and Nico's relationship continues to develop.

A sea of patients flood Grey Sloan Memorial after gunfire goes off at a parade. A blast from the past throws Maggie off her game on the same day that Meredith tries to talk to her about dating Deluca. Meanwhile, Owen and Amelia get some potentially life-altering news about Betty.

A patient gives Meredith some clarity on her dating situation around the holidays. The strain on Bailey and Ben's marriage comes to a head. Meanwhile, Betty drops a bomb on Owen and Amelia.

Amelia and Koracick tackle a daunting surgery on Catherine while Richard and Jackson hope for the best. Meanwhile, Richard urges Meredith to visit her father, Thatcher, before his time is up.

Meredith questions Link's laid-back approach over a patient's treatment. Maggie worries that Richard, Jackson and Catherine haven't come to terms with Catherine's diagnosis. Meanwhile, Deluca steps up in the O.R. when Owen faces a setback.

The windstorm continues to blow through Seattle; and after the power goes out at Grey Sloan, the doctors are left scrambling to save their patients' lives, including Meredith who desperately needs to get to Cece for her heart transplant. Meanwhile, Owen, Amelia and Teddy confront their complicated situation.

Seattle is hit by a huge wind storm and Grey Sloan becomes inundated with patients. Alex and Jo are stuck at home and decide to make the best of it by having a second honeymoon, while Meredith confronts Richard about getting his life back on track.

Catherine is in Los Angeles getting the new foundation ready and summons Meredith and Koracick to visit for a highly confidential consult. Meanwhile, one of the nurses is 28 weeks pregnant and collapses at the hospital while talking to Richard.

Meredith has a patient whose family is celebrating Day of the Dead, making the doctors remember loved ones they have lost. Richard shares unexpected news with Meredith about her father, Thatcher. Meanwhile, Teddy tries to tell Owen that she is pregnant but they get sidetracked, and Jo encourages Link to pursue one of the doctors.

Meredith reaches out to Teddy and helps her talk through some of her personal struggles. Owen and Amelia hide out near Betty's school after she becomes a flight risk. Meanwhile, Jo wants to get to work on the fellowship, but Bailey's attention is elsewhere.

Meredith turns heads when she shows up to work done up and ready for her blind date later that day, while Alex makes a questionable decision in order to save a patient. Meanwhile, the burden of knowing Teddy's secret keeps Maggie up at night, ultimately making her decide she has to tell someone.

Meredith works on a patient who happens to specialize in matchmaking, and a seemingly drunk patient pushes Richard's buttons and gives him a medical mystery to solve. Meanwhile, Maggie tries to reach Teddy after bearing the burden of her secret becomes overwhelming as she struggles with issues in her own personal life.

New doctors continue to shake up the hospital in typical Grey Sloan manner. Meredith bonds with a patient while Jackson struggles with the meaning behind recent experiences; and after making a life-changing decision, Jo forms an unexpected alliance.

The doctors at Grey Sloan Memorial vie for a new position. Meredith is seemingly distracted and struggles to stay focused, and Maggie finds herself the keeper of a big secret while Amelia and Owen try to figure out their relationship. Meanwhile, Jo and Alex's honeymoon doesn't go exactly as planned.