Once upon a time, there was a cop show about a smart, sexy, independent female sleuth with a turbulent past and a handsome, slightly-clingy male "partner" in crime. The pair solved cases, exchanged witty one-liners, and tried not to have sex with one other despite the palpable cloud of URST constantly floating overhead. I'm referring, of course, to Moonlighting Bones Castle. That's right, Castle. Castle is the original boy-girl cop show.

Kidding! Moonlighting was around long before Bones and Castle showed up on our screens. One might even argue that Maddie Hayes (Cybill Shepherd) and David Addison (Bruce Willis) practically invented URST, or at least the modern-day television version of it. Back in 1985, these two taught the world to flirt—and Bones (Emily Deschanel), Booth (David Boreanaz), Castle (Nathan Fillion), and Beckett (Stana Katic) owe their URST-y success to the original dynamic duo.

But the Moonlighting folks messed up when they hooked up Maddie and David at the end of Season 3. Presumably, Bones has avoided that mistake and kept Bones and Booth at a safe distance (well, except for that kiss and that coma dream) for five seasons. Some would say the show has gotten too frustrating to watch, even though the chemistry between Deschanel and Boreanaz is as cute as ever. So where does that leave Castle?

Castle and Beckett have been dancing the delicious will-they-won't-they waltz throughout their first two seasons together, and each episode inches us closer to the possibility of a hookup. In Monday's episode, "The Third Man," the two even abandoned their individual dates to return to the case they were working on... together. And after solving the case, they left the precinct arm-in-arm to grab dinner. It's obvious they find each other attractive—Castle regularly gushes in Beckett's general direction, and lately Beckett hasn't been so subtle in masking her jealousy of Castle's many women.