Given the lukewarm temperature of everyone's favorite couple at the end of last week's Castle - which was swapped with this one out of respect for the Boston bombings - it seemed like maybe their relationship hit a sour note during this week's, "Still."

However, nothing could be further from the truth. That makes the timeline feel a bit wonky, but otherwise this is a fun episode for die hard fans in particular.

Actually, this feels more like what the typical 100th episode could've been: A look back at all of the show's memorable moments via a (sort of) clips show. The apartment Beckett (Stana Katic) is trapped in might be rigged to blow, but the episode is armed with a plethora of music montage flashbacks from seasons gone by.

And the central point of the flashbacks? Well, they're partly to distract Beckett from the fact that one false move could blow she and the apartment building she's in to kingdom come. More importantly, though, it's to settle an argument: Who loved whom first, Beckett or Castle (Nathan Fillion)? The clips were centered on themes such as inappropriate things they said to one another, how "irresistible" Castle was from the beginning, and what Beckett's friends and random strangers had to say about the pair.

Meanwhile, Ryan (Seamus Dever) and Esposito (Jon Huertas) work feverishly to track down any leads to help Capt. Frank Mahoney (Allan Louis) and his bomb squad unearth the code that will disarm the bomb. This becomes even more tricky when bomber Archibald Fosse (Stefan Marks) takes his own life. Castle refuses to leave Kate's side, but that doesn't mean he's not puzzling out the case in his own mind, insisting that Fosse's story is what they should be focusing on.

One of the best montages centers on how Kate's detective skills and Castle's storyteller mind combine forces to solve each case, though there also seems to be a grain of truth to the fact that Castle is a tad addicted to the fun he has getting to hang out with cops. The journey back through some of his wilder conjectures is nothing short of hilarious. Still, he's right, and in the end it's the story that always matters.

In this case, Fosse's story is a sad one even for a killer. He's dying of stage four brain cancer and his last desire is to track down his son, a boy born while Fosse was locked up the first time. Tracking down information on his former girlfriend, he leaves a trail of bombings in his wake of people who didn't deliver the data he wanted, and in the end, he dies before reaching his goal. Discovering the story, however, gives Castle the son's name, which turns out to be the key to disarming the bomb so that they can all walk away unscathed.

There's nothing particularly grand or profound about this episode, but it's a nice tribute to so much of what makes this show enjoyable for so many.

Like most shows, it started out with its weak points but it's grown over time, and like Kate's hairstyle, the show has evolved into something quite pleasing to the eye. The snags last week and the potential job move mentioned in the trailer for the next episode are more than likely just a few more twists and turns on a journey that is, as Kate says, just beginning.

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Castle airs Mondays @10pm on ABC.