The Return - Joining Forces
Professor X summons the team to reassemble to rescue a fellow mutant in Japan in the opener of the anime series following the adventures of a group of superheroes.
Aired 01/04/2011EP 1 - The Return - Joining Forces
2011
X-Men
The X-Men are reunited following the death of a teammate, and are summoned by Charles Xavier to Japan following the abduction of Hisako Ichiki (Armor). There, they confront the U-Men, a lunatic cult that steals and transplants mutant organs to further strengthen their own army, and the battle for justice is on.
(Source: Marvel)