Castle Scares Up a Ghost Story -- and Some Always-Frightening Relationship Talk!

This Monday at 10/9c, ABC’s Castle serves up a Halloween-themed treat when a renowned “ghost hunter” type is killed under legitimately spooky circumstances. As such, the far-out case prompts Beckett, Castle et al to disclose their individual opinions on the supernatural.

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“What we’re dealing with is a murder inside a old, locked haunted mansion, where the only way somebody could have killed this guy was is if they were not of this world — if they were from the other side,” series creator Andrew W. Marlow told TVLine when we visited the set during filming. “So we get to investigate and have a lot of fun with that.”

Being among the highly imaginative, Castle, as one might imagine, “believes that a ghost is behind the murder,” Stana Katic shared, “and Beckett doesn’t.”

Katic, though, teases with a big grin, “That doesn’t necessarily mean Beckett doesn’t believe in the supernatural, which I think is kinda cool.”

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On the topic of frightful subject matter: The episode also features a double date — between Detectives Ryan and Esposito and their respective lady loves, Jenny and Lanie – that takes an awkward turn when the M-word comes up.

Ryan’s fiancée Jenny (played by Juliana Dever) “mentions marriage in front of Esposito and Lanie (Tamala Jones) — something along the lines of, ‘So when are you guys getting married?'” Seamus Dever previews. “And that becomes like a time bomb.”

Adds Jon Huertas, who plays Esposito, “Some things are said that probably shouldn’t have been said in that moment, and it sparks a conversation between Esposito and Lanie that neither one of them were ready to have.”

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Regardless of the uneasy dinner date banter, the detectives’ portrayers were thrilled to delve into their character’s personal lives.

“It’s a lot of fun to get [Esposito, Ryan and Lanie] out of the workplace, and add in Jenny,” says Huertas. “You don’t see them outside of work much!”