As the film begins, a commander is shown traveling through space and discovers life on a planet. He was assigned a task to go to that planet and notices the life there? He lands his spaceship on that plant and moves forward to check, and his two companions were there to assist him. ''Lightyear'' was talking to his companion on phone but few roots attack his other companion under the land.
As their attention divert to their companion the roots attack them from the other side. They were cutting them with their weapon and few things were flying towards them to attack. They make themselves invisible to escape from them. Reaching there, they were about to close the ship's door but ''Lightyear'' sees his other companion. He moves to save her but while saving her his weapon falls from his hand and he gets stuck there as well. His companion in the spaceship gives him her weapon due to which ''Light Year'' comes into the spaceship with his companion while cutting the roots.
He drives it but their spaceship falls there because of being collapsed with a mountain. They discover the crystal of their spaceship is broken with which they can move back to their world. Now everyone from the sleeping pod of the spaceship were taken out safely because of its breakage. ''Lightyear'' was considering himself responsible for all this and feels everyone is stuck here because of him and they are in danger. His companion explains to him that thinking like this is pointless, and that he knows he is capable of creating the crystal. After it, we will be able to go back home.
They finally made the crystal in four years with the things they have and using the planet's powers but now the huge task is to check the crystal and he wants to check it while connecting it with his spaceship. For this, he has to take a round of space in his ship and has to come back on this planet while completing his travel in four minutes. He drives the spaceship and increases its speed and this will work with the crystal he has made but the crystal was giving only 70 percent energy to spaceship instead of 100 percent and that's the reason his test fails.
He comes back to the plant and discovers he has covered this distance in four years instead of four minutes because the time on this planet is faster than the time in space. He finds the gift from his companion when he reaches the room, it was a robotic cat who was telling him about itself. ''Lightyear'' gets tired so he sleeps but he becomes worried to see that time in his dreams, when everyone got stuck here because of his mistake. He again moves on his mission while asking his cat to repair the crystal and performs many new experiments one by one and in all this, 62 years passed.
His companion died but ''Lightyear'' was still young, his companion was saying him goodbye in her last video message. Meanwhile, their new commander is seen on this planet who says to ''Lightyear'' you don't need to waste your time for this useless task. Help us in our new mission in which we are making this place suitable for humans while living here, so humans will stay here easily while escaping from the environment and things. ''Lightyear'' refuses the commander and comes to his cat who was telling him that it has finally made the crystal after the hard work of 62 years. Before he could do something the companions of the commander comes to take the cat but ''Lightyear'' somehow makes the crystal with the cat's method in the lab and leaves for his experiment with it.
The commander stops him but he ignores him, when he returns to his planet he discovers a huge ship has attacked his planet. ''Izzy'' saves him from the enemy attack who was the granddaughter of his friend and companion as well. She tells him you have returned after 22 years this time and this ship has attacked here a week ago and tells they also want to attack the place that we have made safe for the humans. That's why none of their attack become successful to ruin that place but now the people of ''Lightyear'' who were living on this planet, you may call them his family were stuck in that area. ''Izzy''' takes him to her area where they want to take the crystal while moving to their safe place so they will move to Earth while taking it but ''Lightyear'' discovers from the machine on his hand that there is an old spaceship at a distance and they come to take it, as there were few spacesuits inside it.
''Lightyear'' and his companions wear them but this time, a creature of that planet attacks them. They take their spaceship towards the sky while escaping but another spaceship attacks them and they fall down because of it and their crystal also falls down, now their enemies have it. ''Lightyear'' was also caught by the enemies, the face of the enemy of ''Lightyear'' is shown, and he was actually ''Lightyear'' but he came from future. He is an old ''Lightyear'' who is now in front of himself and there was his cat with him given by his companion. The old ''Lightyear'' says to the young ''Lightyear'' that I come from the future and tells his story when he comes after becoming successful in his experiment.
His experiment becomes successful that means they can go back home now but as we saw in the previous scene that ''Lightyear's'' commander was stopping him to perform experiments. The commander will arrest him when he will go back but ''Lightyear'' doesn't want this so he uses his crystal's powers and moves to space through his ship then reaches the future due to some reason. Everything was advanced there and the old ''Lightyear'' says to ''Lightyear'' that I thought if we can come into the future through the crystal, then we can stop the spaceship to come to this planet while moving into the past.
They can stop the whole thing that happened at the start of the movie when they came on this spaceship and they will not face any trouble while moving straight into the world. The young ''Lightyear'' likes this idea and the old ''Lightyear'' says I would have move to the past but my crystal gets damaged while reaching here and if we have to move to the past I will need your crystal for this. Here, ''Lightyear'' gives him the crystal and their mission was about to start but the young "Lightyear" remembers that if they go back in time, he will never meet "Izzy," his companion's granddaughter.
Thinking this, he runs with his crystal but the old ''Lightyear'' tries to capture him through his robot. During this, the young ''Lightyear'' made the ship of the old ''Lightyear'' ready to destroy now the ship would destroy after a short time and after it, he moves out with his crystal while setting the ship to destroy. ''Izzy'' also arrives to save him but the old ''Lightyear'' was still behind the crystal. ''Izzy'' and the team of the young ''Lightyear'' sit in a ship but ''Lightyear'' couldn't reach the ship so he sits in a plane to escape and the plane was caught by the old ''Lightyear''.
He even takes his crystal from his plane and now the young ''Lightyear'' moves out of the plane to escape now he has ended the old ''Lightyear'' with the help of his suit. His crystal also destroyed in this war and the others have also landed their ship somehow with the help of ''Lightyear''. Now after releasing their planet from the old ''Lightyear'', their commander assigns them the mission in which they have to make this place suitable for humans. "Lightyear" also abandons his attempt to return to Earth due to the crystal's breakage. Because now it will take many years to make a new crystal again. Similarly, he was on a new mission with his new friends. This concludes the movie story.
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