The Pro Heroes, All Might, Eraserhead, Present Mic and Midnight were all contacted by principal Nezu, telling them that he set up a meeting with a high-security villain in Tartarus, though he didn't tell them why, but they made their way to Tartarus as instructed by Nezu.
The four heroes now sit in the car as Eraserhead drives, getting the go ahead by the heavily armed guards, they drive into the secure prison, exiting the car and entering the prison.
Upon entering, they see three other pro heroes: Mirko, Hawks and Endeavor.
Hawks: "Ah, you four are here too?"
All Might: "Ah, hello, Hawks. Were you also called in for a meeting with this high-security villain?"
Endeavor: "...We were, yes."
Midnight and Mic look around the heavily secure prison, the amount of security was insane but justified. Eraserhead just stands to the side, his expression blank and Mirko has her arms crossed over her chest, annoyed.