King Ghidorah has returned to Earth with a new ally; SpaceGodzilla. The two plan on unleashing an army of mass-produced MechaGodzilla soldiers to destroy Godzilla once and for all. But that's not all they have planned. Ghidorah has a secret weapon from another dimension, and plans on unleashing it on Earth. Godzilla must take on his greatest challenges yet, but his life will also be changed forever by yet another family secret, as well as his recent marriage to Mothra. This may be his final war.