^Err... okay. What happened there?
Damn, I wish those Japanese classes in college had stuck with me...
A year ago, 34 super sentai gathered to fight off an attack by the zangyack. They used all their powers to seal/fend off the invasion.
The Gokaiger's arrive and are wanted by the zangyack.
So now the gokaiger's meet the past sentai and help them regain their power.
I'm waiting for subs to explain how the gokaiger's have ranger keys in the beginning