Bulma is able to produce another time machine using the capsule. She tells them that it is the time machine that Cell used. The recap of "Dragon Ball Super" episode 51 showcases Mai's backstory and how brutal Black Goku is.
Warning: This article contains major spoilers for "Dragon Ball Super" episode 51. Read to know more.
"Dragon Ball Super" episode 51 recap
The episode titled "Feelings That Transcend Time - Trunks and Mai" starts with Bulma and others talking about Cell's time machine. Future Trunks is the one who restored the time machine in a capsule. And in the future, Bulma wants to keep it so that she can learn more about time travel. However, she is not able to figure out how it works and she gives up. But, in the present, she has Future Bulma's notes and she can use it to restore the machine.
Goku and others can go to the future to fight Black, however, it will take time for Bulma to complete the repairs. Meanwhile, Goku asks Whis to train him but Whis is no mood as they have all the time machines to worry about. Piccolo tells Goku that he can train with Vegeta. But, Vegeta's situation doesn't appear to be training-friendly.
In "Dragon Ball Super" episode 51, Goku heads to Kaio's planet and requests for training. But, Kaio is mad at him for ruining the planet.
Elsewhere, in the future, Black Goku reveals that the battle memories have become a part of his body and mind. He is now aware of Goku's body and moves.
Black Goku wants to know more about his opponent as the knowledge will make him stronger.
In the present, Bulma's parents are back from the vacation and they are shocked to see the garden which has witnessed the battle between Goku and Black Goku.
They meet Future Trunks while Bulma asks her dad to help her out in repairing the machine. She also ropes in the Pilaf gang and Pilaf starts to scheme about using the technology to build a machine for world domination.
Future Trunks hears Mai's name from Pilaf and soon they (Trunks and Mai) share a moment. Meanwhile, Bulma returns to her lab and asks Kuririn and Piccolo to clean the garden.
Mai, Present Trunks and Future Trunks are alone and Trunks shares Mai's backstory with them.
In the future, Trunks met Mai when Mai was on a mission to kill Black Goku who has killed half of the world with his first strike. The remaining Earthlings have joined forces to fight Black Goku.
Mai is the leader of a group and they decide to lure the enemy into a trap. However, the plan backfires after Black is able to emerge unharmed out of the debris. He is able to locate Mai and prepares to attack. Trunks arrive and Black, but he is turning out to be powerful for Trunks.
Black reveals that he considers human beings as Gods' only failure and he must wipe them out to create the perfect world.
Mai is able to distract Black using a flare gun and she disappears with Trunks. Later, Future Trunks tells Mai and Present Trunks that he could not save Future Mai in an attack by Black.
Elsewhere, Shu and Pilaf ask Future Trunks about their future. Trunks has no idea about them. Goku returns and tells everybody how Kaio treated him and he is hungry.
Bulma asks Pilaf gang to clean up the time machine. Mai is blushing as she talks to Future Trunks and Bulma tells that kid Mai talks like an older woman.
Meanwhile, Beerus and Whis are talking about Black's ki and how they had felt it before. In the new episode, "Dragon Ball Super" episode 52, Goku, Beerus and Whis head to Universe 10.
Read more: "Dragon Ball Super" episode 52 preview trailer and summary.
"Dragon Ball Super" episodes air Sundays on Fuji TV.