When aliens invade Saga, Franchouchou doesn't panic, they lean into the absurdity with the same deadpan confidence that made the TV series work. The movie understands that zombie idols fighting extraterrestrials is exactly as ridiculous as zombie idols saving a dying prefecture, and commits to that energy without apology. Concert sequences animate like they matter, Tae finally gets actual character moments instead of bit parts, and the comedy lands hardest when the stakes are simultaneously the highest and the most nonsensical. Some fans will reject the alien plot as a tonal break. It isn't, it's the show doing what it always does: treat the impossible like it's just another Tuesday in Saga.

Franchouchou's biggest moment arrives when they're tapped as ambassadors for Saga's massive 2025 Expo, their performance at the SAGA Arena poised to be the event's centerpiece. Then an alien warship descends on the prefecture, decimating everything in its path with overwhelming force. While the zombie idols scramble to process the invasion, something unexpected happens: Tae Yamada, the one member who never fully regained her consciousness as the undead, suddenly awakens with complete awareness and walks away from the group. Tae's departure fractures Franchouchou just when they need each other most. Determined to face the extraterrestrial threat alone, she ventures into the heart of enemy territory on a solo mission to stop the invasion. The remaining members must decide whether they'll accept their broken group or find a way to reunite and fight back together. What started as their dream showcase becomes a battle for survival where singing and bonds might matter more than anyone expected.