He first meets Joseph who's been wrongfully sent into prison one night and then the next morning, he tells his dream that shows him standing among 3 grape old vines, a tear that fall down from his eye that the vines drinks it in, the grapes became so thick when he picks some grapes and squeezed them into wine and serves them to the Pharaoh. Joseph says that the dream means in three days, Pharaoh will have him released.
Three days later, Butler is released while Baker is taken for his execution. The butler forgets to keep his promise and doesn't tell Pharaoh about Joseph, until the Pharaoh is tormented by dreams he cannot interpret and the butler remembers Joseph and his promise.
The butler is later seen at Joseph and Asenath's wedding. Later seen when Joseph is hosting a feast for his brothers, the butler presents Joseph with his gold chalice.