Five Spies

Five Spies (Japanese title ファイブ) was a 1997 Japanese action series that aired on the NTV television network. The series followed five teenagers who break out of prison with the help of a mysterious benefactor, who then hires them to work as spies as he tries to topple a vast conspiracy. The series starred Tomosaka Rie, Suzukia Sayna, Shinohara Tomoe, Endo Kumiko, Chinen Rina, and Karato Ryo.

Melody of Death! The Terror of Poison Gas! (死の旋律! 毒ガスの恐怖!!) (Season 1, Episode 4)
The spies infiltrate a laboratory as part of their investigation, but when they hack into the computer system, an alarm sounds and Madoka (Rina) is captured. She is hypnotized and brainwashed into helping her captors obtain information on her mysterious employer, Yodobashi (Ryo), and is programmed to kill him.