'Castle' Season 6 Episode 11 Spoilers: Esposito and Ryan's Lives are in Danger [Video]

When "Castle" returns this January, an arson investigation will literally go up in flames.

In a sneak preview of the episode, Castle (Nathan Fillion) and Beckett (Stana Katic) investigate a serial arsonist, which leads them to the home of a pyromanic who runs a website about fire fetishes. The case takes on a tragically personal spin when Castle and Beckett discover that Esposito (Jon Huertas) and Ryan (Seamus Dever) are trapped in a burning building.

The situation then becomes more complicated when Ryan's wife, Jenny--who is played by his real wife, Juliana Dever--goes into labor when Ryan and Esposito are trapped in the building. Dever told TVGuide, "Not only does it look as though Ryan may not be there to watch the birth of his child, he may not live to see the baby at all."

So Lanie (Tamala Jones) and Beckett step in to assist with the baby's delivery.

Series creator Andrew Marlowe also said the next episode will put Castle and Beckett in the spotlight, and will cause Beckett to reflect on what it means to be with someone high profile.

"We have some fun coming up in episode 11," Marlowe teased. "It puts Castle and Beckett in a world in which the spotlight is very bright. And we examine what it does to people. And I think it makes Beckett reflect on what it means to be with a guy who is in the public eye. So that's really fun."

James Brolin will then guest star on the Jan. 13 episode as Jackson Hunt, Rick Castle's (Nathan Fillion) estranged father. He meets his son's fiancee, Beckett, but she is unaware that the CIA operative is her future father-in-law, as he has to keep his identity secret to protect his work. "That introduction comes later and is far more awkward," Fillion hinted.

"[Beckett] has a big question about Jackson's true motives," Katic said. "He's not all that he seems."

Jackson's shadiness comes at Brolin's request, who only agreed to reprise the role if the character was a bit darker.

"I wanted viewers to find out how deadly he is," Brolin said. "He gets a thrill out of terminating people who deserve it. The thrill is there, with no feeling of remorse."

He also said that he "talks down to his son like he's five years old," and "is very attracted to Kate. That's the kind of a--hole he is."

Jackson will also come face-to-face with Martha, Castle's mother, for the first time since their night together long ago.

Additionally, Marlowe told TVGuide that both Senator Bracken (Jack Coleman) and the presumably dead 3XK killer could complicate Castle and Beckett's wedding plans. But, on the Jan. 27 episode, Beckett will find her perfect bridal gown.

"Beckett's past comes back and brings the dress to her," Katic said. "She comes across the gown while investigating a case set in the world of high fashion."

Marlowe said that trying on the dress "is an emotional moment for her [Beckett] because this is something she would have been doing with her [deceased] mother."

"Titanic" actress Frances Fisher will guest star as the person who brings Beckett the perfect wedding dress. She will play fashion mogul Matilda King in the episode, which "has a little 'Devil Wears Prada' feel to it with an Anna Wintour-type character," Marlowe told TV Guide Magazine.

Beckett and her team will bump into King while investigating a murder. It will be revealed that the two women know each other from when Kate did modeling as a teenager in high school.

"Castle" returns on Monday, Jan. 6, 2014 on ABC.