Friday is one of two captured men taken by a group of cannibals to the shores of Robinson Crusoe's island. Crusoe sees them arrive. He watches as they kill one of the captives. The other, being untied, races into the woods to try to escape. When Crusoe sees men in pursuit, he shoots one of them who is coming straight towards him and aiming his bow and arrow at him. He stuns the other one by hitting him on the head. Friday quickly beheads this man.

Friday thanks Crusoe for saving him, and Crusoe turns Friday into his servant. This fits with Crusoe's deep desire to have slaves. Ever since he first saw groups of natives rowing now and then to the shore of his island, he dreamed of capturing one or more to work for him. He is delighted to find Friday, whom he finds a superior native, somewhat European looking, compliant, and eager to serve him.

Friday provides Crusoe with companionship, which up to this point had only been offered by his animals. Friday fulfills Crusoe's fantasy of what native people should be: simple, naïve creatures who look up to Europeans with admiration and wish to serve them.