Meredith (Ellen Pompeo) and Jo (Camilla Luddington) have been working together on a project for the Grey Sloan Memorial research contest, but hit a roadblock when they realized a man in Spain owned the patent they needed.
At the beginning of the episode, Meredith is confident she will be able to persuade the man to sell her the patent but later loses her confidence when it's revealed his daughter will be coming in his place, and they can't find any information about her online.
When she arrives however, things took a turn.
"Mer Mer?" the woman asks.
"Auntie Marie?" Meredith says as she goes in for a hug.
"Twist," Jo jokes.
It is revealed later that the last time Meredith and Marie saw each other was on her eighth birthday, when she decorated Meredith's entirely with balloons. Dr. Marie Cerone (Rachel Ticotin) reveals that her and Ellis Grey were best friends when Meredith was growing up.
But Marie moved away because her father wanted her to run his business back in Spain.
"I really wanted to get in touch when I heard about Ellis," Marie says. "I've watched you all these years. She would've been really proud of you.. she really would have."
Fans were surprised to see someone from Meredith's past she remembered fondly, considering her troubled childhood.
Crying at the thought of Ellis being proud of Meredith #greysanatomy— Hell On Heels (@HellOnHeelsGirl) March 9, 2018
Seeing Meredith happy makes me happy😩#GreysAnatomy— Shanelle💫 (@Chefkay97) March 9, 2018
At first Marie refuses to to sell Meredith the patent because she thinks that her project is a fantasy, but Meredith shows her a test mouse who is already showing progress from the study and she is impressed.
"You really are your mother's daughter," Marie says to Meredith.
The twists didn't stop there, as Richard (James Pickens Jr.) reveals Marie actually hated Meredith's mother, meaning Meredith's study could be in jeopardy.
I knew that went too well smh #GreysAnatomy— Michelle (@ChelleShocked_) March 9, 2018
Grey's Anatomy airs Thursdays at 8 p.m. on ABC.