The Summer I Turned Pretty Season 3 introduced Mia, but she was never part of the third book, We'll Always Have Summer. The final season of the Amazon Prime Video series continued Steven Conklin's story while his sister, Belly (Lola Tung), navigated through a complex love triangle dynamic between her childhood crush, Conrad Fisher, and his brother, Jeremiah. While Steven only played a minor role in Jenny Han's novels, the series fleshed him out even further by exploring his dynamic with Belly even more and putting the spotlight on his on-again, off-again relationship with Belly's best friend, Taylor Jewel.
The Summer I Turned Pretty Season 2 ended with Steven and Taylor finally getting together in a relationship, but it didn't last long because Season 3, Episode 1 revealed that they had already broken up for unknown reasons. The premiere also confirmed that Steven and Taylor now have new relationships, making it complicated for them to get back together.
Created by Jenny Han, The Summer I Turned Pretty features up-and-coming stars Lola Tung, Gavin Casalegno, Christopher Briney, Sean Kaufman, Rain Spencer, and Jackie Chung. Season 3 premiered on Prime Video on July 16, 2025.
Who Is Mia In 'Summer I Turned Pretty' Season 3?
The Summer I Turned Pretty Season 3's premiere revealed that Steven has a new girlfriend: Mia.
She was mentioned several times throughout the episode, but it was clear that Steven had no genuine romantic feelings for her because he was still casually hooking up with his ex, Taylor, quite frequently. Taylor was also in a relationship with a guy named Davis (who was a minor character from the books).
Not much is known about how Mia and Steven ended up together, but it's a safe bet that they started their relationship during the show's three-year time jump between Seasons 2 and 3.
Mia did not appear on-screen in the first two episodes of The Summer I Turned Pretty Season 3 (an actress was not cast for the role, according to IMDb), and she was also not a character from the books. She seemed to be created solely for the series to show how much Steven loves Taylor, even after they broke u (read more about the six biggest spoilers from The Summer I Turned Pretty Book 3).
Summer I Turned Pretty Season 3, Episode 2 Reveals True Reason Why Steven Broke Up With Mia
After Belly found out that Steven was cheating in his relationship with Mia, she confronted him about it, and he was forced into telling her why and how he started hooking up with Taylor.
While he was still dating Mia, Steven met Taylor again in New York, and they started to rekindle their romance. The casual hookups became consistent, and Steven realized that he was slowly falling in love again with Taylor, which is why he decided to make things right by breaking up with Mia in Season 3, Episode 2.
After breaking up with his girlfriend, Steven tried to confess his true feelings to Taylor, but an argument between them ensued, leading to a horrific accident that almost ended his life (he ended up in a temporary comatose state after the incident).
The accident made Taylor realize she was in love with Steven after all, but Episode 2's ending revealed that Steven did not want to chase her anymore because he believed he didn't deserve her.
It remains to be seen if Steven and Taylor will end up together in The Summer I Turned Pretty Season 3, but Jenny Han did tease that a happy ending might be in the cards for both of them. For context, the third book, We'll Always Have Summer, didn't specify who Steven ended up with, so the series has a lot of freedom for the characters' romantic fate.
