Fox is considering the return of The X-Files, Prison Break, and another installment of one of its most successful franchises 24, but 24 could be lacking their leading actor Kiefer Sutherland. Fox discussed the future of these series at the Television Critics Association’s winter press tour on Saturday.

Fox Television Group chairman-CEO Dana Walden and Gary Newman said that the network is currently in rebuilding mode. They added that conversations involving the revival of The X-Files with Chris Carter and a limited run of Prison Break have occurred.

Fox’s current issue with the revival of The X-Files is timing. Creator Chris Carter, whose Amazon series The After was canceled before it premiered, and actors Gillian Anderson and David Duchovny would need to return to get the series rolling again. Newman said that there was nothing Fox could announce at the winter press tour, but they “hope” they can bring the show back to television.

Newman made it clear that he wants Prison Break, which stars Wentworth Miller and Dominic Purcell, to return to the screen. Newman said that there has been some speculation in the press at the return of Prison Break and the studio wants to bring it back. He said that Prison Break is the “perfect event series.” However, like for The X-Files, Fox does not have any news at this time.

As for 24, Sutherland has outwardly expressed his interest in retiring from his days as Jack Bauer, which lasted for eight seasons, generated the 12-episode Live Another Day and a TV movie. Sutherland told USA Today in September that his “bones are creaking.” And he has suggested that the show continue without him.

Since Sutherland has no desire to continue, the network is discussing ideas. Walden said that producers Manny Coto, Evan Katz and Howard Gordon gave a “great pitch” for a possible 2016 return. The pitch was said to have been able to go with or without Sutherland. Walden said that the pitch obtained a point were Jack Bauer could fit very organically, or they could prepare for his absence.

Walden said that Sutherland will only “potentially” not be in the upcoming installment of 24. Walden added that it was hard to know since the team is in the early stages of development. They are not talking about continuing the show without Jack Bauer, but they are considering whether he will be in the next installment.

Walden said at Fox’s portion of the Television Critics Association’s winter press tour that they would be relying on exciting storytelling and their unique “real-time element” to keep viewers hooked. She also implied that Yvonne Strahovski and Mary Lynn Rajskub will continue on the show.

She praised the creative team and the show’s characters, and she said that she has considered everyone around Sutherland in the previous installment and she thinks “it could work” without him. However, Walden said that they will be taking their time with the revival.

Newman expressed his love for the show. He said that Fox would “love nothing more than to do another 24,” and he called the matter a “constant focus” for Fox.