After a strange incident, the Phantom Thieves wander into a bizarre realm where its citizens are living under tyrannical oppression in Persona 5 Tactica. Surrounded by a military group named Legionnaires, they find themselves in grave danger until a mysterious revolutionary named Erina rescues them and offers an enticing deal in exchange for their help. What truth lies behind Erina and the deal she offers to the Phantom Thieves?