Castle

Love brings out the best — and the worst — in us.

Monday’s pre-Valentine’s Day Castle, Season 4, Episode 15, “Pandora,” showed us Kate Beckett’s (Stana Katic) darker — or shall we say greener? — side when she came face-to-face with Castle’s (Nathan Fillion) original muse: sexy CIA operative Sophia Turner. Ain't nothing like finding out you weren’t actually the first.

Below, peep Kate Beckett’s best (and by best we should probably say worst) moments of jealousy from Season 4, Episode 15, “Pandora.”

5. Don’t Mess With My Man

Second after their initial meeting, Beckett notices gorgeous CIA agent Sophia giving Castle a lil’ extra attention and shoots her that “don’t mess with my man” look we’ve all seen at one point or another. In this case, it was cute. Kind of.

4. Mirrored Muses

As if Beckett wasn’t freaked out enough that Castle and Sophia have a past, she’s even more furious when she finds out Castle modeled one of his characters, Clara Strike, after her.

“Castle wanted an up-close-and-personal look at a female CIA agent. And I gave him one,” Sophia croons as Castle anxiously slurps his coffee. Um, whoa!

Later, Beckett cuts in with this gem of a jab, shooting Castle a look of contempt: “I hate to break up this reunion, but we’re being illegally detained. Or at least, I am.”

3. Same Team?

Castle can sense something’s not right with his partner-in-crime (solving). In the elevator on the way out of the CIA, Castle brings up Beckett’s discomfort with the Sophia situation and tries to persuade her that the three of them are in this together.

“We're all on the same team here,” says Castle, hopefully. “No we're not. You're on her team because the way you look at her, you're sure as hell not on mine,” Beckett responds.

Straight to the point.

2. “How Many Woman Have You Semi-Stalked in the Name of Research?”

Beckett and Castle broach the subject of his relationship with Sophia a few times during the ep. This time, Castle tries to convince Beckett his relationship with Turner was NBD.

“I was young and she had a lot to teach me,” Castle says to which Beckett responds, “Yeah. I bet.” But when she asks how long the duo actually worked together, Castle admits it’s was a year-long affair.

"How many other women have you semi-stalked in the interest of research?" Beckett retorts. Need some ice for that burn, Rick?

1. Independent Woman

We all know Kate Beckett is one self-sufficient lil' lady. Rick wants to press the “panic” button on his cell phone that’s directly connected to Sophia/the CIA, but Beckett says, “I’m not going to be rescued by your girlfriend,” says Beckett.

We have a feeling that sentiment might change when she finds herself trapped in a car underwater …