The protagonist, named Michael Schmidt, takes a job advertised in the newspaper at a local family pizzeria called Freddy Fazbear's Pizza. The advertisement states that he will be responsible for the safety of the equipment within the restaurant, including the animatronic entertainers – Freddy Fazbear, Bonnie the Bunny, Chicka the Chicken, and Foxy the Pirate Fox.
Upon arriving on his first night, Schmidt receives a prerecorded message from the previous night watchman, who welcomes him to the company and reads a statement from the company for legal reasons. Despite the bored and deadpan tone in the watchman's voice, the topics he covers are unsettling, such as how the restaurant will not be liable for dismemberment and how the carpets must be bleached of blood. After he assures Schmidt that it is not as bad as it sounds, he informs the player that the animatronic animals are set to a free roaming mode at night in order to prevent their servo motors from seizing up. They used to be allowed to wander as such during the day, but an incident occurred in 1987 called "The Bite of '87", in which an animatronic bit and seriously wounded a customer. Also, the previous watchman informs Schmidt that if the animatronics see him, they will mistake him for a metal endoskeleton without its appropriate costume and find it as "against the rules at Freddy Fazbear's Pizza". Therefore, they will forcefully stuff Schmidt inside a spare costume, and due to the costumes containing many support structures for said endoskeletons, Schmidt would be essentially crushed to death.
As the game progresses, the antagonists become more aggressive and quicker in their pursuits and make attempts to capture Schmidt more frequently and in less predictable ways. If Schmidt survives for five nights, he receives a paycheck for $120.
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