Lennon era uno degli Altri che ha trovato rifugio al Tempio. Faceva da traduttore per Dogen ed è stato ucciso da Sayid alla sorgente un attimo prima che l'Uomo in Nero invadesse il Tempio (Massacro del Tempio) ("Tramonto")
2007 (Sesta stagione)Modifica
When Jack, Kate, Hurley, Jin, and Sayid arrived at the Temple, Dogen ordered the Others, through Lennon, to shoot them. Hurley, however, announced that Jacob had sent them and wanted Sayid to be healed. Lennon then asked for proof that the group was sent by Jacob. Hurley produced a guitar case containing a wooden ankh. Inside the ankh was a paper, presumably listing the survivors' names, among other unspecified information regarding Sayid.
Lennon later on was present when Sayid was taken into the spring to be healed, and, following Sayid's death, told everybody that he wasn't able to be saved. He led Hurley to Dogen's chamber deep within the Temple, where he learned that Jacob was dead. Lennon assisted The Others in preparing the Temple's defenses, and told Hurley the goal was to "keep 'him' out".
Lennon was then sent, along with several armed Others, to retrieve Jack so that Dogen could speak with him. As Lennon tried to convince Jack to come with him, Sayid suddenly sat up, alive, much to Lennon's surprise. ("Los Angeles LA X, seconda parte")
After conferring with Dogen about this turn of events, Lennon summoned Sayid to Dogen's room, where Sayid was promptly tortured. Lennon informed Sayid that it had simply been a "test", and that he had "passed". As Sayid left, Lennon observed that he had just lied to him. ("Quello che fa Kate")
Later, when Sayid delivered a message to the Others that the Man in Black would kill anyone left in the Temple at sundown, Lennon tried to calm the Others down and talk them out of leaving. He was confident that the Man in Black could not get into the Temple. However, this changed after Sayid killed Dogen: Lennon burst into the room and was dismayed to see Dogen dead, saying that Dogen was the only thing keeping the Man in Black out. With a swift movement, Sayid slit Lennon's throat, killing him. ("Tramonto")
- Durante il casting è stato descritto come "Uomo, dai 30 ai 50, qualsiasi etnia. Trasandato, nervoso e carismatico, riesce ad essere deferente al bisogno; potrebbe essere stato mentalmente squilibrato. Portavoce e traduttore per il capo di una società sconosciuta. Facilita i compiti. E' un negoziatore molto furbo ed è più potente di quello che sembra per la sua posizione...." 
- Indossa lo stesso tipo di occhiali del musicista John Lennon (con cui condivide il nome), che era famoso anche per quelli.