The episode begins with Rip Hunter leading Commander Steel to Manhattan in 1965. He explains the task at hand of protecting the Spear of Destiny, and Henry hands Rip his dog tags to give to his wife and son. The two part ways.
Rip, Nate, Amaya, and Sara follow close behind, failing to find Henry.
The four walk onto the Waverider. They determine that Henry's new identity might be a test pilot working for NASA. They find a newspaper clipping that proves that Henry was working on Apollo 13. Rip walks in, and they determine that they need to break into NASA and free Henry.
Sara, Amaya, and Nate are led on a tour through NASA's facilities. Ray and Rip stand in front of a press conference that Henry is about to give. Rip approaches Henry, who punches him in the face. Rip is escorted out of the building.
Rip is sent to a holding room. Henry explains to Ray that the punch was because of something between him and Rip. Sara, Amaya, and Nate walk in and greet Henry, who asks for an explanation. They explain what's been happening with the Spear of Destiny, and Henry explains that he hid his piece of the spear in the safest place possible - inside the flag that Neal Armstrong planted on the moon. The Legends then ask if Henry is going to help save the Apollo 13 mission, but Henry explains that it launched without a hitch - meaning that history has changed.
A group of astronauts sit on Apollo 13. One quickly sedates the other two and reveals himself to be Eobard Thawne.
The team determine that they need to stop Apollo 13 before it lands on the moon. In the meantime, Henry introduces Mick, Stein, and Jax to the mission control crew, claiming they are from the British space program.
Henry and the rest of the Legends take the Waverider into space. Ray tries to make small talk with Henry, but he storms off. Nate follows him, and discovers that Henry is upset because Rip's mission has kept him from his family. Henry suggests that Rip will be able to drop him back in the 1950s as if he never left his family.
The group determine their plan to infiltrate Apollo 13. Ray shrinks down to enter the spacecraft, and finds Thawne exiting the ship to land on the moon. Sara tells Ray to stay hidden from Thawne, but Thawne has already spotted him.
Rip turns to full size and fights Thawne in the space capsule. A button is accidentally pressed, sending the capsule apart from the rest of the ship. Ray is forced to fly the capsule onto the moon.
At mission control, Stein and Mick try to determine a way to distract the crew so they don't see Ray land on the moon. They begin singing, long enough for Ray to land the capsule without NASA noticing.
Sara asks if Ray is okay, but he explains that the capsule doesn't have enough fuel to launch back into space. He determines that he will find the piece of the spear while Thawne is tied up in the capsule.
Nate and Amaya talk about whether or not Henry should be returned to the timeline. Nate assures that even though he normally doesn't want to mess with history, bringing Henry back would help improve the relationship between him and his dad.
Sara notices an oncoming meteor shower. The Waverider takes the capsule to safety, but Sara and Rip argue about whether or not the ship will absorb the meteor blast. Meteors hit the ship, shutting off Gideon's controls and sending the ship floating into space.
Ray places a footprint of his Atom suit onto the surface of the moon. He proceeds to run and jump towards the American flag planted there. He takes the flag out, finding the piece of the spear hidden inside. He announces that he found the piece, and the team informs him that the Waverider is damaged and that Ray will need to make the jump ship be able to fly again in order to leave the moon.
Ray begins a video diary explaining his situation. Eobard stops him, reassuring that he will help work together with Ray to power the jump ship.
Amaya confronts Henry, explaining that him returning to the 50s would create a time aberration, possibly changing who Nate is as a person. Henry asks why Nate didn't tell him before, and Nate says it was because he wants to protect his family more than history itself. Nate tells Amaya about the fate of her family, and asks if she would make the same choice in her situation.
Henry apologizes to Rip for being angry with him before, saying that he now realizes that leaving his wife and son was a mistake. Rip apologizes for making Henry sacrifice so much. Henry then praises Rip for helping the Legends get along since he saw them in the 50s, and Rip explains that it was Sara who did that, not him.
Eobard laments to Ray about how he likes working with fellow scientists. Ray calls Eobard a monster, but Eobard assures that the two of them are more alike than they think.
Sara phones in to Ray, who explains that he and Eobard have the capsule ready. Stein directs the team through the launch, which goes off perfectly.
The Waverider sends Apollo 13 safely back to Earth. Mick notices that Stein is unhappy about that, and Stein explains that the Waverider is damaged and will probably not be able to return home safely.
Ray and Eobard enter the ship, with Sara, Amaya, and Rip all pointing guns at him. They escort him through the ship.
Stein leads Sara through the safe re-entry of the ship.
A young boy walks through mission control. It's Hank, Henry's son and Nate's father. Henry explains that he fixed an essay contest to bring Hank to mission control so he could actually meet him.
Stein explains that the ship will need a super computer to help them calculate what angle to pilot the Waverider. Ray rushes to Thawne, who gives him an answer - 38 degrees.
The team debates about whether or not to trust Thawne's calculations. Rip agrees to let Sara make the decision. After reassuring that Ray trusts Thawne, Sara agrees to follow the calculations.
Sara pilots the Waverider through re-entry. Rip and Stein determine that opening the cargo bay door will send enough pressure to propel the ship back to earth, but that whoever does it will die. Both Rip and Sara volunteer, but Henry has beat them to it. Rip instructs him on how to open the cargo bay door.
Nate runs to the door and begs him not to do it, but Henry explains that he has fulfilled his destiny by protecting the spear, and can die with peace. He asks Nate to send a message to Hank, and he pulls the door open, flinging to his death.
The ship is brought back to Earth. Amaya runs to Nate, who cries on her shoulder.
Thawne phases out of the Waverider's prison. He is met with Ray, holding an anti-speedster gun. Ray explains that he realizes that he is a time remnant who should be dead after Eddie's death, but is being chased by Black Flash. Thawne is notified that Black Flash is close to his location, and he speeds away from Ray.
Mission control celebrates a successful landing of Apollo 13. Nate walks through and approaches young Hank. The two talk about the astronauts, and Nate notices that Hank is wearing Henry's dog tags. Hank explains that he never knew his dad, while Nate explains his dad's dislike towards him. Hank feels sorry for him, and Nate tells him that if he keeps that lesson in mind, he will be a better man for himself and his son.
Sara finds Rip drinking in the captain's office. She thanks him for supporting her decisions during the mission, and he explains that it's been hard for him to come to terms with the fact that Sara is a better captain than he ever was. He explains that he feels like he's out of place if he's not the team's captain, but Sara reminds him that the whole team is full of people who don't fit in. They look to each other and toast.
Amaya apologizes to Nate for telling Henry about the consequences of his return. Nate says that Henry would have sacrificed himself anyway. Nate apologizes for telling Amaya about her future, but she explains that she's aware that her future is bigger than herself. The pair hug.
Amaya asks Gideon to pull up the Zambezi records that start after her return home. Gideon warns her against it, and Amaya asks her to do it anyway. She discovers what happens to her future granddaughter, Mari.