After obtaining a mysterious portal Gun, Blue gets sent across the multiverse, corrupting it, while attempting to capture the Stikbot who gave him the teleporting device to begin with.
Following the first film, Now that Blue has wrecked the universe he must repair it with the help of Yellow, and finally put a stop to Silver.
After the events of the second film, Blue has been cloned and now must face against his evil clone, while teaming up with some unlikely allies on the way. To now ACTUALLY repair the universe once and for all...