Pardon Us is a 1931 American PreCode Laurel and Hardy film. It was the duos first feature length comedy film, produced by Hal Roach and Stan Laurel, directed by James Parrott, and originally distributed by MGM in 1931.
Laurel amp Hardy are assigned to attend prison school with James Finlayson being the teacher. The vaudeville routine that follows ends with a spitball meant for somebody else hitting the teacher in the face and the boys wind up in solitary. There is a sustained scene of the bleak cells with the unseen boys conversing through the walls.The prison authorities decide to send Laurel to the prison dentist to have the offending tooth pulled, but the dentist is incompetent and the procedure goes awry. ........
Source: Wikipedia