The Rookie's Nathan Fillion has revealed he will appear in the first episode of spin-off series The Rookie: Feds.
Teasing that he doesn't believe "it's a spoiler," he took to Instagram for a video with co-star Melissa O'Neill to share that they were on the second day of production for season five and getting used to a new studio lot where season five will film.
WATCH: The Rookie: Feds coming this fall
"So much to report!" Melissa captioned the post, adding: "In the mean time… here’s a little hey-hello from @nathanfillion and I on the lot today. Such a treat to be back at it with our @therookieabc fam!!!"
In the video they both were riding on the back of a golf cart. 'It's officially day two on season five of The Rookie," said Melissa before Nathan shared he has spent day one filming on the spin-off with Niecy Nash.
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"It's our first spin off ever of The Rookie and hopefully not our last," he added. Fans were quick to comment as did co-star Jenna Dewan who left heart emojis.
The Rookie: Feds stars Niecy as Simone Clark, the oldest rookie in the FBI Academy. Introduced in season four of The Rookie with a two-episode arc, Clark proved popular with viewers and the new show was ordered to series and will air on Thursdays in the fall.
Nathan and Melissa shared the video with fans
The Rookie will continue to air on Sundays, dropping on 25 September.
Feds also stars Frankie Faison, who plays Christopher “Cutty” Clark; and Felix Solis, as Special Agent Matthew Garza, both of whom also starred in the backdoor episodes.
Britt Robertson was confirmed this week as a new member of the cast.
Simone Clark was introduced in The Rookie
Britt, known to audiences for The Secret Circle and starring opposite George Clooney in Tomorrowland, will play Laura Stensen, the "black sheep of a family of brilliant academics and the youngest person ever allowed into the FBI’s behavioral analysis unit."
Described as "socially awkward" and a "workaholic" she is given a lifeline in the unit after discovering her boyfriend has been cheating on her and falling into a slump.