During a hostage drill in a bank, Ian, the police captain, reveals that all main entrances and fire exits are sealed, leaving the team to use the vent shaft as an alternate entry point. Ian orders sevoflurane, a colorless, odorless anesthetic, to be released through the vents to incapacitate the robber and hostages. Inside, the man holding hostages, Jake, remains unaware and focused on his notes. However, the Commissioner grows concerned when the live footage shows Jake suddenly moving as if sensing something, raising suspicion that he may have detected the gas despite its invisibility.