John Nolan has had several romances over the course of The Rookie, with some being much more beloved than others. How do they all stack up?

Season4 of The Rookie may only have a few episodes left, but fans of the Nathan Fillion crime drama will be relieved to know the show has been renewed for a fifth season. In addition to fighting crime, protagonist John Mulaney has had several romantic storylines, and he is just as dedicated to his relationships as he is to the LAPD.

Relationships don't always work out, and while it's heartbreaking, it's often for the better. There are several great couples in The Rookie, as well as those who had fans campaigning for a breakup. Nolan hasn't always had the best luck when it comes to matters of the heart, but some of his relationships are more successful than others.

5 Lucy Chen

While Lucy is easily the most likable character in The Rookie, her romance with Nolan is a facet of the show that most viewers don't care to dwell on. The relationship is forced from the beginning, and their chemistry is simply non-existent. Lucy and Nolan fall for one another at the police academy and continue to date in secret after becoming rookies at Mid-Wilshire.

The two only break up to protect Lucy's career, but she eventually comes to realize she shouldn't let the opinions of others dictate her actions. Regardless of her development, their feelings for each other haven't been revisited since the first season. In fact, it's easy to forget they dated at all. Nolan and Lucy's relationship takes such a platonic turn, it almost seems as if the show is actively trying to erase their history.

4 Sarah Nolan

Viewers first learn about Nolan's ex-wife during the pilot, but Sarah doesn't make an in-person appearance until season 3's "Brave Heart." Emily Deschanel was a phenomenal choice for the role, as her show Bones and Fillion's Castle were both major crime dramas airing during the same time period. The leads finally get to share the screen, even if the circumstances are less than ideal.

In one of the most tear-jerking episodes of the series, Nolan and Sarah are forced to stand idly by while their son fights for his life. With Henry being the only thing that ties them together, it's clear that the two aren't compatible. However, the actors play off of each other well, and it could be entertaining to further explore their onscreen dynamic.

3 Grace Sawyer

Grace isn't the most popular character among viewers, but her relationship with Nolan has a complicated history. While Nolan and Sarah have better onscreen chemistry, their marriage came from a place of obligation. The couple parts ways after high school, as Nolan falls for Grace during college. However, Sarah's unexpected pregnancy changes everything.

Although his heart lies with Grace, Nolan marries Sarah so they can raise Henry together. Grace and Nolan's love story is left unfinished, so it's only fair that the show gives them a second chance. Much of Nolan's character arc in The Rookie season 2 is linked to his old flame, making their relationship a pretty significant one. The two clearly aren't meant to be, but they no longer have to spend decades wondering "what if."

2 Jessica Russo

Jessica has always been a good match for Nola,n and the couple showed serious long-term potential. Not even Grace reentering Nolan's life breaks them apart, as the bond they form is difficult to compete with. Nolan and Jessica are forced to overcome several obstacles, but they always come out stronger on the other side. They split due to circumstances outside of their control, which only makes their ending all the more heartbreaking.

Jessica realizes that she wants to be a mom, and fears she's running out of time to make it happen. Because Nolan has just uprooted his life to begin a new career, he isn't in the right place to raise a child. He's already a father and doesn't feel the immediate need to expand his family. Unfortunately, Jessica can't afford to wait until Nolan is ready, causing them to call things off. Although their breakup is upsetting, it's better they split amicably than risk resenting each other down the line.

1 Bailey Nune

Not only is Bailey Nolan's best love interest, but she's also exactly what fans needed in The Rookie season 4. Her storyline is often independent of Nolan, and she seamlessly fits into the narrative. Bailey isn't reduced to the main character's love interest ⁠— she just happens to be in a relationship with him. Her job as a firefighter and past in the army reserve makes her heavy presence in the show organic and believable.

First responders work together more often than not, and Nolan and Bailey are able to interact both on and off the clock. Out of all of his relationships, Nolan's romance with Bailey appears to be the most promising. She's the most stable love interest he's had throughout all four seasons and it's hard to imagine them breaking up. The couple faces plenty of issues but is always on each other's side at the end of the day. Nolan stands by Bailey when her husband tries to frame her, and Bailey supports Nolan in whatever he chooses to take on next.

NEXT: Most Upsetting Character Deaths On The Rookie, Ranked

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