The cast and creators of “Party Down” had a secret up their sleeves.

While promoting the third season of the once cancelled series, almost everyone involved in the revival of “Party Down” was tight-lipped about the absence of original star Lizzy Caplan.

Creator and EP John Enbom previously told Variety that Caplan was “booked through the entire window that we had” and was “bummed that she was not able to join us.” He also said, “we were bummed, too – we really liked working with her.”

However, everyone seemed to keep her cameo appearance a giant secret at the end of the season’s sixth and final episode.

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“I can’t believe that they were able to keep it a secret,” Caplan surprisedly told Variety in a post-credits interview. “There are no secrets these days!”

Production pulled off Caplan’s cameo during a “sneaky day” in which Caplan was on set for “Fleishman Is in Trouble”.

Caplan discussed how tight the schedule was for the day, explaining: “It was all we could do. We really managed to shoehorn this in. I was committed to “Fleishman Is in Trouble” in New York, and I was more than willing to travel on off-days to come back to L.A. and make “Party Down” happen.

“But with COVID, they really didn’t want anybody traveling anywhere. It was heartbreakingly impossible. So I just hoped that [the “Party Down” team] ended up making something so wonderful that Starz would have no option but to pick it up for a fourth season. I have to say, having watched all the episodes, I fully believe they did their job.”