The following contains spoilers for The Rookie Season 5, Episode 1, "Double Down," which debuted Sunday, Sept. 25 on ABC.

The Rookie fans hoping for Chenford tuned in eagerly to Season 5, but Chen and Bradford's romance hinted at in the previous season finale stalled in the premiere. Viewers angry at yet another delay shouldn't blame the ABC show's writers -- blame a misunderstood reason for the collapse of Moonlighting, the network's biggest hit in the 1980s.

While The Rookie is unique among police procedurals for its focus on street-level cops, romance was baked into the concept from the beginning. Producers realized that Melissa O'Neil's character Lucy Chen needed to be a part of that story, but her first choice of partner almost doomed the series. Luckily, the show was able to develop Chen's character further -- and point her toward her former training officer Tim Bradford, in large part to O'Neil and Eric Winter's on-screen chemistry. Ater years of hashtags and fancams, the characters finally kissed at the end of Season 4. But the circumstances around that kiss are poised to keep the two apart, likely because of a long-held (but wrong) theory in TV history: The reason Moonlighting declined in ratings is because the two main characters hooked up.

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What Was Moonlighting and Why Is It Relevant to The Rookie?

Tim and Lucy go undercover on The Rookie

Moonlighting debuted in 1985 and followed former model Maddie Hayes (Cybill Shepherd) and investigator David Addison (Bruce Willis). Its stories were less about the mystery of the week and more about how David and Maddie would flirt relentlessly while solving the crime. Initially a huge hit, the show's ratings faltered in the later seasons seemingly because the characters became romantically involved. While Moonlighting has disappeared from view, every TV couple now frustratingly dances around a relationship until the end of a show's run.

This isn't even Nathan Fillion's first network crime procedural loved by the shippers. Castle -- also an ABC production -- seemed to prove the theory. Richard Castle professed his love to Kate Beckett, he eventually reciprocated, they got married... then the show ended unceremoniously and disappointed fans. But that's far too reductive. While rumors persist about the set of Castle, Moonlighting producer Jay Daniel said in a fanzine interview that the on-set tension was unbearable. Eventually series creator Glenn Gordon Caron threatened to leave during a fight with Shepherd, and ABC let him walk. That the decline in the quality of both series happened after the characters "got together" is a coincidence. The Rookie's storytellers can put Bradford and Chen together, they just have to know what to do afterward.

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What Does This Mean in The Rookie Season 5?

The Rookie Angela and Wesley

The smart money says that The Rookie's long-term undercover assignment and the return of Annie Wersching's fan-favorite serial killer Rosalind Dyer will push any Chenford action to later in the season. But one other contributor to a decline in fan interest after a romantic pairing is that the show waited too long to give it to them. Castle fans had to endure delay after delay to their relationship in the name of tension. Similarly, Moonlighting inexplicably had Maddie get married in Season 4 after she and David slept together.

There is a fine line between giving the fans a star-struck love story and messing with their emotions in a way that makes the viewing experience no longer fun. The Rookie risks alienating all the Chenford shippers if they keep toying with the relationship. It undercuts all the subtle character work that made fans want the pairing in the first place, especially since they had the perfect setup in Season 4. And making Chenford official is less of a risk for The Rookie than it was for Castle or Moonlighting. The Rookie is full of romantic relationships, so things can be comfy and cozy in at least three households with only one in chaos at a time. Chen and Bradford have every reason to get together, except for that one pesky off-screen misconception.

The Rookie airs Sundays at 10:00 p.m. on ABC.