Hannibal Chew/Sloat works for the Tyrell Corporation/Rosen Association/Van Ness Pet Hospital. His job is to create the eyes for the replicants. As an eye designer for Tyrell, Chew designed the eyes of Roy Batty and Leon Kowalski. In the film, as he is creating his artificial eyes, he receives unwelcome guests: Roy and Leon. At first he is merely angered and shouts at them that it is illegal for them to enter, but he soon learns that they are replicants because they are unaffected by the frozen conditions of his lab. Leon rips open the jacket that he wears, exposing him to the cold and interrogate him while he freezes. Roy and Leon find out from him that J.F. Sebastian/John R. Isidore can get them into Eldon Tyrell/Rosen's inner sanctum. It is unlikely that Chew survives the encounter (nor presumably whoever was tending the store out front).
Chew was played by James Hong, who reprised his role in the Blade Runner (video game) as well. In the video game it is revealed that he lives next to the designer of the replicants' skin, Moraji and that they eat dinner every night until Moraji is killed by a bomb planted by Sadik.
James Hong has said that there was a scene left unfilmed where Chew is found frozen solid, is accidentally knocked over and broken into many pieces on the floor.