Castle Season 5, Episode 5: "Probable Cause" brought the return of a familiar face — the infamous Triple Killer, aka 3XK. Unfortunately, the episode didn't give us the closure we'd hoped for, as the psychotic serial killer disappeared without a trace.

Like most die-hard Castle fans, we're anxious to know what really happened to 3XK and whether or not he'll rear his head again. When Wetpaint Entertainment questioned show creator Andrew Marlowe, he remained relatively tight-lipped about the elusive murderer, but he did drop a few hints.

Wetpaint Entertainment: All of Season 5 has been very fun so far, except for the 3XK killer episode. Are you getting tired of fun?

Andrew Marlowe: No. But I think that we need to ground the series every so often. You shouldn't be having too much fun investigating murders all the time. Every now and then, you kind of get down to brass tacks, but we're really delighted with the balance of shows that we have this year so far.

Do you think there will be more dark episodes?

Well, we'll have a handful of dark episodes by the end of the season, but somewhat fewer than we had last year. Last year was a little bit more an angsty season that we wanted the balance to be tilted a little bit more towards fun this season and exploring the relationships. But that being said, we feel like our more serious episodes have their own special feeling and special place in fans’ hearts. And one of the things that we really enjoy about our show is that it has such a wide dynamic range. It can actually accommodate serious shows, fun shows, tense shows, so we love playing in all the different sandboxes.

We love how fun the show is this season. The humor is really great.

You can't have dark episodes all the time. They're great relief to the fun stuff, but it also helps make the fun stuff that much more fun.

Is 3XK someone you want to revisit within the rest of Season 5?

Maybe. Let's just say I haven't ruled it out, but he may be dead. Castle may have killed him. I don't know.

He's not dead.

We'll see.

What do you think happened to 3XK? Is he alive or did he sink to the bottom of the East River? Tell us your theories below!


Wanna chat with fellow Castle fans? Join the discussion on our Castle Facebook page!
Follow @CastleWetpaint on Twitter



More About Castle
Castle Spoilers
Castle Season 5
Castle Episode Guide