Numerous theories have offered possible explanations about where Cal (Jack Messina) went in the two-part Manifest season 3 finale. Despite the protestations of his family and the Eureka scientists, Cal touched the tailfin and disappeared. When he returned at the end of the finale, he was suddenly five years older.

What happened with Cal set a new status quo for his character and may have also set a new direction for the Flight 828 passengers. Now played by Ty Doran, Cal claims to have the answers now. During Grace’s dying moments, Cal appeared at her side and said he knows what they have to do now. If that’s true, Cal could have developed a proper understanding of the Callings and how they’re supposed to use them to stop the Death Date. Since the beginning of the series, a lack of knowledge about what’s going on has been the characters’ biggest problem. If Cal’s disappearance has allowed him to overcome this obstacle, this development could very well be the key to saving the Lifeboat.

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The answers Cal will have for Ben (Josh Dallas) and the others are sure to be vital to Manifest season 4 – as will the show’s explanation for what happened to him. Cal vanishing and coming back five years older points to time travel, but where (and when) he went remains unclear for the time being. Where was Cal for five years of his life, and how did being there help him solve the mystery of the Callings? Here’s every major theory on where Cal teleported to at the end of Manifest season 3.

Cal Time Traveled To The Future

Cal on the plane in Manifest.

When Cal returned, he seemed upset – but not surprised – to find his mother dying in their house. This detail has led to the assumption that Cal knew it was going to happen. If so, it could be that Cal has been living in the future somewhere. If Angelina (Holly Taylor) already killed Grace (Athena Karkanis) at the point in the timeline where Cal was, that would make sense of his awareness of the situation and his reason for being there at the right time. Having lived in the future, Cal could know the fates of all the main characters, including Grace and the time of her death. And if Cal is aware of how the passengers ultimately deal with the Death Date in June 2024, that could be how he knows what they’re supposed to do next.

It's worth noting that the prospect of Cal spending time in the future matches with what normally happens when a character on Manifest disappears. The plane left in 2013 and came back in 2018. Zeke (Matt Long) seemingly died in a blizzard in 2017, before showing up alive a year later. All things considered, Cal being sent forward in time would be consistent with what’s transpired so far in the series.

Cal Time Traveled Five Years Into The Past

Cal wearing a black sweatshirt in Manifest.

There’s no precedence for a Manifest character going backward in time (yet), but that doesn’t necessarily mean Cal won’t be the first. A common theory regarding Cal’s whereabouts in the season 3 finale postulates that he was sent five years into the past. If that’s the case, Cal could have grown up somewhere else in the country using a different name and possibly living with a different family. Cal could have spent those five years studying Al-Zuras, the history of the Callings, and other related incidents. Having this much time to do research could have enabled Cal to make a tremendous amount of progress when it comes to understanding the Callings.

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Cal going to the past would be the only explanation that wouldn’t involve two separate uses of time travel. For example, Cal being in the future would mean that he must have found a way back to the present. But if Cal had gone to the past instead, he may simply have remained there, biding his time until the day of his disappearance. Cal may have known that there couldn’t be two versions of the same person in the Stones’ lives at once.

Cal Lost Five Years Of His Life

Cal and Olive looking through papers in the basement in Manifest.

Manifest showrunner Jeff Rake’s comments on Cal’s disappearance have created a very different interpretation of what happened to him. In an interview, Rake said that Cal sacrificed five years of his life to save the passengers [via TV Insider]. Some think that the meaning here was literal. In other words, Cal didn’t actually go anywhere. Instead, he simply aged up five years to match his correct age. If Flight 828 hadn’t vanished, Cal would be 17 years old. What the tailfin did to Cal may have been a form of cause correction. Arguably the greatest flaw in this theory is Cal’s claim about knowing what to do. It’s hard to imagine that Cal would cultivate the knowledge they need to beat the Death Date in a single instant.

Cal Went To A Parallel Universe

Not all believe that time travel or resurrection is at the heart of Manifest’s central mystery. One idea that picked up a lot of steam over the course of season 3 is the parallel universe concept. Quite a few believe that the Flight 828 passengers really did die in a plane crash, and that the characters featured in the series are actually their counterparts who crossed over from a different timeline. This essentially serves as an alternative explanation to Ben’s resurrection theory. He thinks the plane wreckage at Eureka is evidence that the plane crashed and was somehow reconstructed by a divine phenomenon, but he may be completely wrong about that. The truth may be that there were two planes and two sets of passengers, one from each timeline.

If there really is a parallel universe in Manifest’s world, the show may use Cal to finally delve into this story. It’s possible that when Cal touched the tailfin, he was teleported back to his original timeline, thus allowing him to finish growing up with different versions of Grace and Olive. Ben and Michaela likely wouldn’t have been present, since they disappeared with Cal on Flight 828. After living there for five years, Cal could have intentionally (or perhaps unintentionally) triggered a way to return to the new timeline and help the main characters figure out where to go from here. Cal relating such a story to Ben, Saanvi (Parveen Khaur), and all the rest in Manifest season 4 could help them reach an important realization about the circumstances surrounding Flight 828’s disappearance.

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