Dave was Hurley's imaginary friend, which he hallucinated while an inmate at the Santa Rosa Mental Health Institute. Hurley saw Dave again while on the Island, a setback in his battle against mental illness.
At the Institute
In "Dave", Hurley repeatedly saw Dave and talked about him with his psychiatrist, Dr. Brooks. The doctor said that Dave was a bad influence who tried to keep Hurley from losing weight or changing. He eventually took a photo as Hurley posed with his arm around Dave's shoulder's. The finished photo showed Hurley's arm hanging over empty air, with no sign of Dave.
Despite the photo's revelation, Dave appeared again to Hurley, offering him more food and encouraging him to break out of the facility. Hurley refused, and his later refusals to listen to Dave led to a breakthrough in his therapy and his eventual release.
On the Island
Hurley saw Dave on the Island as the survivors scrambled to gather food from the supply drop. Dave lost a slipper when Hurley chased him through the jungle, and Hurley imagined picking it up. Libby, watching him, saw no slipper.
Dave tried convincing Hurley that he'd never left Santa Rosa and was currently hallucinating his experiences on the Island. He'd based the numbers in the Swan, said Dave, on the numbers he'd heard Leonard Simms mutter, and he'd hallucinated Libby, a woman too attractive to ever actually take interest in him. Dave jumped off a cliff, telling Hurley that doing the same would wake him from his hallucination. Hurley nearly followed suit, but Libby arrived and talked him out of it.
- According to Lost Encyclopedia writer Tara Bennett, the Man in Black impersonated Dave on the island. Dave never existed, negating the Man in Black's usual need for a dead body. Instead, he simply read Hurley's mind. "Hurley was always going to see what he wanted to see anyway," said Bennett, "and the smoke monster could kind of take advantage of that." Damon Lindelof, however, said Dave was a figment of Hurley's imagination "slash-apparition" and had nothing to do with the monster. (Lost Podcast) The published encyclopedia did not say Dave was the Man in Black.
- David is of Hebrew origin, and its meaning is "beloved."
- Dave was intended as a reflection of Hurley's issues with his missing father, David. They both have rascally, happy-go-lucky personalities. Imaginary Dave keeps encouraging Hurley to over-eat; David's last act before leaving his son is giving him a bar of chocolate.
- He is one of three non-main characters to have their name in an episode title. The others are Tricia Tanaka and Ji Yeon Kwon.
- In an interview the executive writers and producers discuss the source of the name "Dave" -
Damon Lindelof: We like certain biblical names and David is one of them. David happened to be my father’s name, maybe that’s sort of subconsciously rattling around in there.
Carlton Cuse: The connection between the imaginary Dave and Dave his father was completely intentional, I mean we wanted basically Hurley to imagine a friend and have that be wrapped up in his unresolved relationship with his Dad, so that’s why his imaginary friend is named Dave.
Damon Lindelof: As to Libby’s ex, that’s an entirely different David we may or may not meet in the future.
- Spiro Razatos - the stunt actor who performed the cliff-falling stunt.