Returning to New York from a family vacation in Jamaica, the Stone family is separated when adult siblings Michaela and Ben, along with Ben's gravely ill son Cal are bumped to a later flight, while Ben's wife, daughter and parents fly ahead. When that later flight lands, the passengers are bewildered to discover that five and a half years have gone by. They attempt to reconnect with the loved ones who mourned their passing and moved on, and try to make sense of a mystifying phenomenon steering them to act in ways they don't understand.
With the detained passengers secretly moved and subjected to painful experimentation - and Cal's health directly linked to them - Ben takes advantage of an old friend to find out where the passengers were taken. Meanwhile, a mysterious new version of the calling pulls Michaela into a murder investigation that has deep personal ramifications for her.
Ben forms an unlikely partnership with Vance in a high-stakes race to locate the missing passengers of Flight 828. Meanwhile, Michaela helps a suicidal passenger who believes he is the Angel of Death, and Cal goes back to school, navigating both his unwanted celebrity and his former friends, who are all now 16 years old.
Michaela's mystifying, next-level calling launches her on a mission that brings her relationship with Jared to a head. Determined to protect his family, Ben explores an alternate meaning to Michaela's calling that leads him to a new alliance and a powerful new adversary. Cal's struggle with Ben's absence from home forces the Stones into an agonizing confrontation that could alter the family's fabric forever.
Willing to follow any lead to keep his son safe from The Major, Ben heeds Cal's calling to help Captain Daly clear his name for what happened to Flight 828. The journey uncovers a seeming conspiracy that stems all the way back to the day the plane disappeared. Meanwhile, Michaela assists Autumn in her own journey of redemption - but has Autumn truly set out to redeem herself, or is she still working against the passengers?
When Cal is discovered missing from his bedroom, Grace and Ben launch a desperate search which takes them to the remote mountains of upstate New York. A tantalizing trail of breadcrumbs leads them to a startling, game-changing discovery. Meanwhile, Michaela confronts the deceptive Autumn, and the shadowy "Major" finally makes an appearance.
As the Stone family reels in the aftermath of a devastating shooting, they’re hit with their most foreboding Calling yet, sending Ben on a mission to locate two Flight 828 passengers who have mysteriously gone missing. Grace grapples with her new pregnancy. The Major attempts to tighten her grip on the unwitting Saanvi.
Ben and Saanvi work together to orchestrate a surprising family reunion for an emotionally closed-off Flight 828 passenger. Olive drifts further away from her family. Jared learns more about a growing cabal of anti-828 sentiment. Michaela finds herself out on a limb when baggage from Zeke’s past threatens to destroy his tenuous new life.