Lockdown Zone: Lv. X

Awakening from an afternoon nap in her family's high-rise apartment, high schooler Ryoka discovers a series of frantic text messages from her mother warning her that the building is under an unprecedented quarantine. Stepping cautiously into the corridor, she finds terrifying, rapidly evolving extraterrestrial lifeforms called X roaming the stairwells and elevator shafts. Every floor presents a nightmarish gauntlet where horrific death resets her back to her bedroom, creating an agonizing time-loop trap. Armed only with her smartphone, sharp deduction instincts, and neighboring survivor Shuhei, Ryoka battles psychological terror to escape the quarantined zone.