Recurring guest star Alex Kingston is set to return as River Song, the Doctor's time-travelling wife in the upcoming Christmas Special of the BBC series "Doctor Who."

In "The Husbands of River Song," the International Business Times reports that River will recruit the Twelfth Doctor (Peter Capaldi) in an intergalactic chase to fight a new alien. The Doctor came out of hiding to help a spaceship that crashed. His wife will reportedly not recognize him, as she has not met his newest reincarnation yet. The Doctor first encountered River back in 2008, when David Tennant was playing the title role. She is the daughter of Rory Pond (Arthur Darvill) and his companion Amy (Karen Gillan).

In the promo pictures, the Doctor and River will be facing a giant robot. It reportedly belongs to King Hydroflax (Greg Davies). He is angry at the pair and will send his bodyguard to capture them. To make matters worse, the machine is out of control. River has a small weapon to fend off the monster, while the Doctor is holding a flashlight that can be the new supersonic screwdriver. Will they get to defeat the new villain? When will River realize that the man she is with is actually her time traveler husband?

In a recent interview with the Radio Times, showrunner Steven Moffat revealed why he decided to bring River back this Christmas. He admitted that he did not want to introduce a new companion for the Doctor so soon after Clara (Jenna Coleman) left.

"I hadn't written River for a couple of years and I'd always loved writing for her and I'd missed her. I thought, given that I'm knackered at the end of a series, what would be a treat for me would be getting Alex Kingston back onto Doctor Who," he said.

The "Doctor Who" Christmas special will air on Friday, Dec. 25, on BBC America.