Undercover agent Saki has been given a new mission. She has to locate the headquarters of a criminal organization, steal their secret data, and destroy their facilities.

This organization performs human trafficking, and Saki lets herself be kidnapped to infiltrate it. This works, but now she has no weapon nor communication device. She is on her own, and she has a mission to complete.

Saki uses cards to choose offensive and defensive actions in the battle to break through each level until she reaches her goal.