Hammer Session! summary: Two prisoners managed to escape after the police truck carrying them crashed on the highway. One of them , Mr Sawazaki (?) is a gangster who has sent 10 opposite bosses to hospital. The other called "You" - our protagonist - is a con artist whose cheating profile has piled up to approximately 100 billion yen. Accidentally, "You" then becomes the new teacher for the nearby high school, under the new name Takeda Shindo, and according to a deal of "Hammer Session" with the headmaster. The story is about a teacher who has a past record as a con-artist. It has its own unique taste, which makes it distinctive from other series about teachers, such as GTO and Gokusen.