Gellert è l'insegnante di scienze di Locke alla Cowin Heights High School. After rescuing 16-year-old John from being locked inside a school locker, Gellert told John that he got a call from Portland by a Dr. Alpert on behalf of Mittelos Laboratories who worked with chemistry and new technologies. Mittelos was looking for young, bright minds and they wanted John to go to their summer camp. When Locke asked how they knew about him, the teacher suggested that they sent a representative to a science fair at Costa Mesa where John had presented a display. John got upset and told Gellert that he was not a scientist, but the type of person who was interested in sports and cars. Gellert kindly told him that even if he wanted to be more like the popular boys at school, it was just not who he was. He said that John simply couldn't be a super-hero, to which John responded "Don't tell me what I can't do!" and walked out. ("Ricerca febbrile")

CuriositàModifica

• Durante il cast venne descritto come: Gellert. Qualsiasi etnia, 30-40 anni. Insegnante di chimica del liceo, intelligente e comprensivo, offre ad uno studente brillante l'occasione della vita, ma si arrabbia quando la sua offerta viene rifiutata. Co-star.

v · d · m John Locke (X)
Interpretato da Terry O'Quinn, Charles Henry Wyson e Caleb Steinmeyer
Episodi dedicati	"La caccia" • "Deus Ex Machina" • "Esodo, terza parte" • "Orientamento" • "Chiusura" • "Ulteriori istruzioni" • "L'uomo di Tallahassee" • "Il brigantino" • "Ricerca febbrile" • "Vita e morte di Jeremy Bentham" • "L'incidente, seconda parte" • "Los Angeles LA X, prima parte" • "Los Angeles LA X, seconda parte" • "Il sostituto" • "L'ultima recluta" • "Il candidato" • "La fine"
Episodi realtà parallela	"Tutti amano Hugo"
Personaggi nei flashback	Matthew Abaddon • Adam • Agente di viaggio • Richard Alpert • Kate Austen • Autumn • Ayesha • Jimmy Bane • Bobby • Cindy Chandler • Padre Chuck • Eddie Colburn • Construction foreman • Anthony Cooper • Crystal • Eddie • Emma • Dottore • Infermiera • Florence • Frainey • Francine • Gellert • Hajer • Helen • Impiegata pubblica • Jacob • Jan • Sayid Jarrah • Noor "Nadia" Abed Jazeem • Bea Jones • JD • Kid • Kim • William Kincaid • Jin-Soo Kwon • Benjamin Linus • Aaron Littleton • Lizzie • Walt Lloyd • Emily Locke • Mrs. Locke • Locke's nurse • Detective Mason • Melissa • Michelle • Mike • Moderatrice • Randy Nations • Helen Norwood • Nurse Margaret • Charlie Pace • Physical therapist • Detective Reed • Shannon Rutherford • Security guard • Jack Shephard • Sister Consuela • Mrs. Talbot • Peter Talbot • Tom • Travel agent • Waiter • Warren • Charles Widmore • Sceriffo Williams • Zach
Oggetti	Backgammon • Bara • Bussola • Cruciverba • Coltello • Fischietto • Lettera di suicidio • Passaporto di Bentham • Sedia a rotelle • Trabucco