“Halloween is not for the faint of heart. There’s a surprise around every corner. Some of the surprises are good. And some of the surprises are bad,” according to Meredith Grey.  And sure, there were some surprises during this episode! Check out some of the highlights from “Thriller” below:

Not so “easy-peasy” – Leah spends the night at Arizona’s place but slips out before breakfast, honoring Arizona’s wishes to keep things between them casual. Later at the hospital, Leah is bit by a “zombie” patient and freaks out at the thought of contracting HIV. Arizona walks in on Leah crying in the locker room and comforts her by sharing a similar story. She tells Leah it’s not the time to be easy-peasy. After her scare, she’s relieved to learn her tests came back negative.

Mummy dearest – Meredith and Derek arrange to throw a party at Meredith’s old house for the families from daycare but both are swamped with their busy schedules. Meredith’s day is booked solid – her grant got approved and she has back-to-back surgeries, leaving Derek to fix Zola’s broken butterfly wing for her costume while also working on his research. Meredith finds Alex in the hallway and questions him about the supplies for the party, which he hasn’t yet purchased. Cristina overhears their conversation so Meredith invites Cristina to the party. After initially declining, she decides to stop by. Once she makes it to the house, she takes a peek inside and drops the cupcakes off. Meredith notices the cupcakes on her way out, realizing that Cristina was there but didn’t decide to stay – or even say hi.

Blurred eyes – Stephanie returns to the hospital after getting LASIK eye surgery. Jackson still believes she needs more time to recover, but Stephanie is anxious to get back into the swing of things. She’s a second year resident, after all. She treats a patient who is suffering from what she believes is a bug bite. Due to her fear of hospitals, she had to be dragged in by her son. Stephanie opens up the wound and finds maggots. She tells Meredith and Callie that she wasn’t sure what it was at first because of her struggling eyesight, forcing the two to have her run errands instead of treating patients. Later at Joe’s, Stephanie still can’t fully see and mistakes Jackson as a random stranger talking to her. Jackson admits he was prepared to spend the whole day taking care of her. Instead of waiting until tomorrow, he wants to start tonight and takes her home.

Ready, set, no – Callie and April are surprised when Owen tells them he’s no longer seeing Emma. Apparently things between them got a little weird after she learned about his ex-wife Cristina – from Cristina! Can you blame her? He later leaves Emma a voicemail, pleading he’s ready and he doesn’t want complicated. She’s simple and he likes that. She immediately calls him back.

The princess astronaut – Callie and Arizona both pick separate costumes for Sofia to wear on Halloween. Sofia told Callie she wanted to be a princess but assured Arizona she wanted to be an astronaut. Due to their ongoing problems, Callie tells Meredith she’s going to steer clear of Halloween this year. After a chat with her patient, Callie decides to put her feelings aside so she can see Sofia and makes it to Meredith and Derek’s party where Sofia is dressed as a space princess.

Webber – Bailey is surprised to learn that Webber wants one of the second year residents to perform his surgery and she’ll be the one to decide who gets it. After listening to Bailey’s rants about the residents, he proposes that she’s in fact the problem by not allowing them to learn. He wants to teach them, so he kicks Bailey off of the case. He pages Meredith into his room to apologize for his recent behavior towards her. Webber also wants her to choose a resident to operate on him. Meredith initially picks Shane, but when he passes on her offer she enlists Jo. She successfully completes the surgery and later walks Webber through her process, allowing Meredith to slip out of the room to make it to her Halloween party.

Ben returns – Ben surprises Bailey at work a few days early because he didn’t want to miss Halloween with his family. He visits Derek and helps him stitch up Zola’s butterfly wings. During their conversation, he proposes an idea to help air the wings out, which inspires Derek to try that same approach for his sensor array. Bailey arrives home that evening to see that Ben and Tucker decorated the house for Halloween. When Tucker runs off to retrieve his trick-or-treat bag, Ben tells Bailey that he dropped out of his residency program to spend more time with his family. After the shock sets in, Bailey admits she’s disappointed in him.

Cristina/Owen – Owen gives Cristina a patient whose organs are completely backwards as a Halloween gift. During their time together, she vents out her frustrations about Meredith to him. Owen tells Cristina to stop overcomplicating things after Meredith texts her to bring cupcakes to the party. Cristina takes Owen’s advice and decides to go. After ditching the party, she ends up at Joe’s and Shane offers to buy her a drink.

Spooky – Shane finds a woman searching for Dr. Brooks. After some spooky encounters, he is finally to treat her. Meredith picks him to perform Webber’s surgery but he refuses, insisting he has to stay with his patient. He informs the woman that Brooks passed away and learns she was secretly treating her. Shane assures her that he’ll be her doctor now.

Jackson/April – The two scrub in on a patient who was bit by the “zombie” to repair the gashes in his face. During surgery, Stephanie continues to text Jackson (even though she keeps misspelling words) but he assures her things will be fine. April is shocked to see how nice Jackson treats Stephanie, but later admits that Jackson being an “ass” to her made her “get her act together.” When their patient wakes up from surgery he rambles about the zombie until April assures him he’ll be just fine. 

Alex/Jo – Even though things between the pair are awkward, Alex and Jo are forced to work together on a patient. Jo tells the patient, who appears sad that she’s going to miss Halloween, not to worry because some of the best trick-or-treating takes place on the Peds floor. Jo confronts Alex for how he’s treating the patient’s father, convinced that he’s taking his personal frustrations against his own father out on him. Later, Jo and Alex rush to find the patient when he learns her body isn’t producing enough adrenaline. If she gets spooked, her whole body could go into shock. They arrive to find her missing from the room. The girl passes out from fear after running into Shane’s patient. Alex finds her lying in the hall and rushes her into the ER. The patient’s father admits he made a bad call but Jo assures him he shouldn’t listen to what Alex says. Jo is later picked to scrub in on Webber’s surgery and spends most of the time venting to Meredith about Alex. She almost tells Meredith about Alex’s dad, but Meredith insists she doesn’t want to know since he confided in Jo and not her. Meredith advises Jo to stick with him. She listens to Meredith and shows up at the house to apologize. Alex lets her in.