Ben leaps into a female airline attendant in First Class when airlines still served prime rib and lobster as in-flight dining. They have a bit of turbulence.

At HQ, Ian protests the direction to shut Ziggy down. They are outvoted and the order goes forward. Ziggy goes offline.

On the flight, Ben is getting acclimated to the service and clientele. Holly, another attendant, gives him some pointers and a pep talk.

Addison checks in with him when he goes to see if anyone in the lounge upstairs needs anything.

Addison explains that Ziggy’s offline but that the handlink still works. She fills Ben in. He has leaped into Lois Mitchell from Chicago. It is August 5, 1971. He is flying from London to New York. When he tells her the flight is Trans Global 349, she informs him the flight crashes in the Atlantic, killing everyone on board.

At HQ, Ian fills Magic and Jenn in on the TGA 349 crash. There is no known reason for the crash although there are theories that weather and mechanical issues played a part.

Ben and Addison try to figure out a way to avoid the crash. Ben takes the coffee tray off of Holly as she’s heading to the cockpit. Holly is reluctant and warns him the flight crew is a little cranky.

Ben tries to encourage the captain to divert the flight due to weather but the captain is confident he can manage the weather. When Ben tries to appeal to the first officer, the captain kicks him out of the cockpit.

Addison discovers the captain is under investigation but she doesn’t know why yet. She pops out to find out. Ben sees Holly drinking an airplane bottle of booze. She says the kid in first class, Cory, is driving her nuts. He’s the son of the airline’s owner.

Cory’s security detail, Leslie, comes to Ben looking for matches for her cigarettes. Addison discovers that Lesley is ex-NYPD and tells Ben to ask for help. Ben doesn’t. Addison asks if this is still about Martinez and Ben’s fear of being too trusting.

At HQ, Jenn discovers the pilot, Jim, had been getting off-the-books electroshock therapy to treat bipolar disorder. Ian shares a Reddit theory that TGA 349 crashed as a result of pilot suicide.

Ben rushes to the cockpit once Addison informs him, and finds the captain poisoned and dying and the engineer already dead.

Ben realizes the first officer never drank his coffee and thus wasn’t poisoned. They’re in a communications deadzone and past the time of the last recorded contact from TGA 349. The first officer says he’ll attempt to make an emergency landing as soon as communication is possible.

Addison tries to convince Ben to ask for help, but he refuses in case he trusts the wrong person again.

Jenn discovers that Holly’s boyfriend has ties to the IRA. Knowing IRA attacks always occur as team efforts, Magic directs Ian to look into the other passengers to find Holly’s partner or partners.

When Ben confronts Holly, she’s shocked and angry he’d accuse her of poisoning the cockpit crew.

Ian and Jenn discuss how they approach their jobs and how shutting Ziggy down felt personal. Ian admits knowing that future them caused everything the team is going through doesn’t help. They’re feeling untethered. Jenn gives them a pep talk.

Cory catches Ben going through Holly’s bags. Ben reminds him he’s in a restricted crew-only area, but he’s used to having the run of the plane.

Cory notices the tamper seal on the emergency equipment storage is broken.

Inside, Ben finds a go-bag belonging to the first officer. Leslie, Cory’s bodyguard joins them. Cory tells her the plane is being hijacked. Turns out she’s part of the plot and pulls a gun on them.

The hijackers take the plane. Leslie makes an announcement stating that they want a ransom and if their demands are met, they’ll let everyone go home safe.

The plan is to land in Cuba.

The team at HQ works out how Ben can save the plane. It’ll take a miracle.

Holly’s still mad at Ben but he convinces her to follow his lead. They enter the cabin and insist the people need water. The mercenary guard allows it but barely.

As he works his way through the cabin, Ben palms a bottle of quaaludes from a zoned out passenger. After chatting with another, he announces she’s about to go into diabetic shock and needs her insulin.

The guard finds Ben in the back but refuses the water he offers him. Instead, he insists that Ben drink the water. Ben drinks it, pours another and throws it in his face, using the distraction to plunge a needle into his neck. He knocks him out with a combo of insulin and quaaludes.

Ben goes to First Class. He finds Cory hyperventilating and convinces the guard to let him talk to the boy.

While Ben’s talking to Cory, the First Class passengers stage a resistance and the guard fires his gun multiple times.

Ben convinces the passengers not to storm the cockpit. He works on creating something to subdue the first officer and Lesley. Addison urges him to ask for help.

He contacts the cockpit and tries to convince the two there to stand down from their plan. They refuse and Ben gives Cory the go-ahead to light the knockout bomb he created. The smoke fills the cockpit and Lesley and the co-pilot collapse.

Sitting in the cockpit, Cory points out the plane’s lost hydraulics. They have five minutes before the plane crashes.

Ian finds a workaround with a manual reroute of the hydraulics. Ben convinces Cory he can manage the hydraulics. Addison goes to watch Cory. She brings in Ian to help Ben land the plane. Ben recognizes and remembers Ian and their karaoke song, Under Pressure.

Ian talks Ben through the landing and they land safely.

At HQ, Ian enters to applause. In the wrap-up, they find out Cory became a successful pilot and enjoyed a long career. The flight team were given commendations and Lois, Ben’s host, was invited to the White House. The four hijackers are still in prison.

Addison is a little sad thinking how they have no idea what’ll happen to Ben.

Ian receives a ping and shares that Ben’s quantum signature is offline. They can’t track him anywhere.

Ben lands in the shattered remains of the Quantum Project HQ. It’s snowing through a hole in the building. A figure approaches and explains it’s a nuclear winter. Ben recognizes Ian, a lot older now. Ian greets him and says they’ve been waiting a long time for him. Ben realizes he’s leaped into the future.