The Frozen UFO was a flying spacecraft that somehow got frozen while flying.
While the UFO was flying, it got frozen somehow, being preserved in ice for a long time, along with frozen animals and other creatures.Ice Age: Collision Course, however, they were seen frozen in different areas. On the other hand, this frozen UFO was found by Scrat, when he was trying to bury his acorn. Once when he buried his acorn he ended up activating the ship, and was blasted into space.
The ship zooms into space and crashes into the Moon, causing it to hit several other planets causing them to bounce around and bump into each other as if they were billiard balls (the Moon is the cue ball) that ends up forming the Solar System which incidentally gives two planets new appearances (Jupiter's Great Red Spot is formed when Mars bumps into it, leaving a red splotch-like bruise on its surface; while Saturn is bumped into its rings as if it were a billiard ball falling into a pocket), as well as causing a green planet to be shot off into space and toward some constellations.
Scrat manages to slow the ship down and is amazed at the "new world" he's in, until one of his tears accidentally reactivates the spaceship. The force pulls him back as he's put into an astronaut suit and released outside the UFO. Scrat witnesses two more extra planets collide with each other, shattering both worlds and forming the Asteroid Belt. After dodging a few hurtling space rocks, Scrat and his acorn then get tied on to the front of the spaceship while it crashes on a rock-like meteoroid, causing Scrat to land on the other side of the planet. Scrat then joyfully places his acorn into the ground and salutes in delight, however, the surface cracks and gives way, causing Scrat to get stuck in his own space helmet after being pulled by the spaceship and holding on to the acorn. Prying himself off, he then watches as half of the asteroid begins to head towards Earth, with his acorn stuck to it. Scrat, in embarrassment and relief, floats away offscreen after his suit breaks away.
Back in space, Scrat managed to get his acorn back and squeeze himself out of his space helmet and into his space suit where he travels through the rubber airline back towards the UFO. Inside, Scrat notices Earth, runs to the front of the ship, and gives the planet and homesick look. Scrat has a moment of silence, until his foot slid down a switch, causing the ship to be launched back away from Earth. Trying to get back to Earth, Scrat pushes multiple buttons, Scrat vs gravity until he activates a gravitational switch, where the UFO creates artificial gravity, causing Scrat, his acorn, and a few devices to float. Scrat then hurries down, to turn the switch off, bringing him and the objects back down. Seeing his acorn, Scrat runs for it, but unknowingly turns the switch back on, only this time, switching it to a gravitational pull. Just when Scrat reaches for his acorn, the gravity pulls him down and he's unable to get his acorn. As Scrat struggles to get back up, his skin gets pulled down revealing his skeleton, and also causes his teeth to to fall, piercing his tongue. Finally, Scrat gets a hold of his acorn, but the acorn starts to roll and rolls over his paw, causing pain because of the gravity pulling it down. Then, the acorn started to roll where Scrat lied. Scrat tried to escape, but the acorn ended up rolling over him. Scrat groaned in pain.
As the UFO flew in Space, Scrat chased his acorn until it landed in a room. Scrat raced over to get it, while powering the room. As Scrat reached for his acorn, the acorn suddenly disappeared, bewildering Scrat. The acorn appeared again in a different area. Scrat ran after it, but the acorn teleported again, back into the previous area. Scrat grabs a hold of it, but then gets teleported with the acorn. He comes back again, with the acorn mutated as his head. Scrat freaks out, running around, until he falls back on the teleporter and gets teleported again. Scrat gets mutated and teleported with his acorn multiple times, including having his acorn as his tail, hands, eyes, uvula, and nipples and also seems to get injured by his acorn.
The teleportation finally stops. Before Scrat tries to get his acorn, he carefully reaches it aware of the teleporters, and destroys the teleporters, preparing to crush one of them with his acorn, until he gets zapped one final time into the bathroom of the UFO, throwing his acorn into the toilet. The toilet ends up flushing the acorn, and releases it outside the UFO. Scrat watches his acorn float in space, screaming in frustration.
Scrat tries to catch his acorn in space, by tractor beaming it. He ends up targeting it, and attracts it to his ship. Apparently, Scrat was also attracting the moon to himself. To avoid this upcoming collision, Scrat swings the attraction and ends up letting go of the moon, causing it to rotate around the around the earth really fast, bringing up the tides. This unexpected action, actually helps The Herd pass under a river that was blocking them from travelling to their destination from saving the world.
Back up in space, Scrat tries to catch his acorn, but ends up missing, attracting an electrical storm that was caused after he made Jupiter received it's red spot. He ends up throwing the electrical storm back to Earth, creating an obstacle for the herd.
Ready to go back to Earth, Scrat prepares for take off, placing his acorn back in the lever, buckling his seat belt, and places blue infused neon space shades. Scrat targets Earth, and takes off. As he travels back to his home, he notices that the asteroid is in the way, and he ends up crashing straight into it, causing it to move faster to Earth.
Neil deBuck Weasel then takes us to Mars to show that it was once a hospitable planet. He explains that it used to look a lot like Earth. He ends up questioning what had happened to the planet, where all the water and life form had went. This changes when Scrat shows up, unable to keep control of his ship and dries the place out, wiping out all vegetation, water and other life form on the planet, making it uninhabitable. It kills strange mars creatures, one witnessing it all. Realizing what he had done, Scrat acts like nothing happens, returns back to his ship, then flees.
Scrat appears again with his acorn, but his snout gets slammed by a door. When he tries to get his acorn, he ends up getting beaten by the door several times, until he quickly runs through. Scrat grabs his acorn and blows a raspberry at the door, until it opens vertically, smacking him. This causes the acorn to bounce into a room where there are several doors that stands between the acorn and Scrat. Scrat, looking shocked, slowly gets up and groans, walking towards the next door. Scrat's yells are then heard as the UFO flies through space.