Before Nathan Fillion was Rick Castle on “Castle,” he spent a year wandering through space and avoiding the law as captain of the Serenity on Joss Whedon’s sci-fi-Western series “Firefly.” On his current show, Fillion’s character works alongside the law solving crimes that, for the most, stay on Earth. But in a coming episode of the ABC series’ Season 7, Fillion’s Castle might have to return to space with his new wife Beckett (Stana Katic) to solve a case.

According to TV Line, Katic recently revealed that a future episode of the current season might take the couple to another planet – Mars. The episode, appropriately titled “The Wrong Stuff” – in reference to the classic 1983 astronaut movie – will send Castle and Beckett to the Red Planet, Katic told the site at HBO’s Golden Globes party. Katic said the interplanetary episode would involve “spacesuits and space travel.” There is no plot synopsis for the episode just yet, but it sounds like it should be a good one.

The bigger question is whether or not the couple will be working together on their Mars mission. Currently, Castle is working as a licensed private investigator while on suspension from the police after the midseason finale in December, when his Mafia ties got a man killed. On the next episode, “Private Eye Caramba,” Castle will get his first real client when an actress on the set of a telenovela, where a woman was just killed, contacts him about a missing purse. The gig will give him the chance to hang around Beckett, who will also be investigating the murder.

“Castle” airs Mondays at 10 p.m. EST on ABC.

Will Castle ever get back in the good graces of the police? Will Castle and Beckett really go to Mars? Fans will have to wait and see to find out. Tweet your thoughts to @Ja9GarofaloTV.