- Played by Madison
BEFORE THE CRASH
- Walt's Yellow Labrador Retriever
- Original owner was Brian Porter, Walt's adoptive father
- Michael takes Vincent from Brian without asking after Susan dies and tells Walt that Brian gave him the dog. He does this both as an act to console his son and out of his contempt for Brian.
- Presumably was in the luggage compartment of the aircraft
ON THE ISLAND
- First seen by Jack after the crash wandering free in the forest
- Was brought back after the crash by Locke when he blew a whistle he carved.
- Was placed in the care of Shannon by Walt before he left on the raft.
- Since Walt is gone, Michael is gone, and Shannon is dead has become friends with Ana-Lucia or at least when she has food.
- Changes owners a lot.
- Was present right before Sun was attacked but didn't bark or defend her. It is possible that if he was still in the area he recognized Charlie and didn't see any reason for alarm.
- Searching for Vincent is often used by the show's writers as motivation for the island residents to venture into the jungle.
- Vincent returns to the beach in S.O.S. just before Michael returns in the jungle with Jack and Kate
Theories
- Possibly related to one of the mysteries on the Island. Evidence: Season 1 Episode 2 - When Boone, Shannon, Charlie, Sawyer, Kate and Sayid move out for the hill to receive a signal with the transceiver, they are watched by Vincent (the camera points on Vincent hiding in high grass).
- Possible is the "eyes" of the others. People speculate that he is somehow a spy planted in the group by the others.
- Javier Grillo-Marxuach called Vincent "the dog of doom", perhaps signifying that his appearances are bad omens.