The upcoming seventh season of ABC's Castle will feature an alternate reality episode in which the series will address a different timeline for Castle (Nathan Fillion) and Beckett (Stana Katic) in which they never met.

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The sixth episode of the new season of Castle will be an "alternate reality" episode in which the engaged detectives have not met at all. Jon Huertas, who plays Esposito on the series, told TVLine that the episode is his favorite of the new season.

While the first few episodes will be more heavy on drama, Huertas said that "this 'alternate universe' is classic Castle, where you mix a great procedural crime with comedy."

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He added that the episode will show "a completely different world" in which each of the characters will appear, though in different configurations. "It was a lot of fun, getting into that script and seeing how we might all be a bit different. It's a really fun episode, and people are really going to enjoy it. It's one of those episodes where you have to laugh."

Very few details are known about the new episode, though as Enstars previously reported, it is titled Time of Our Lives.

The first few episodes of the season will likely focus on Castle's car wreck, which concluded the sixth season of the show in May.

Castle Season 7 is set to premiere on Monday, Sept. 29 at 10 p.m. ET/PT on ABC.

Watch the promo for the new season of Castle here: