Father Martinez is the religious dictator of Santa Clara. He rose to power after Lasher left Santa Clara to spread the word of the Holy Flame with Morpheus. A cruel and manipulative man, Martinez has the public following his every command out of fear of the dreaded "El Diablo". El Diablo is, in fact, a Deathclaw that The Church captured and holds under the Chapel. Martinez warns that El Diablo punishes sinners, and in order to be safe, the public must follow his every command.
Martinez has a rivalry with leader of The Sinners, Miguel. Depending on the actions of the player, Martinez is either killed by the Vault Dweller or regains control of Santa Clara until it ultimately perishes due to his failure in leadership.
Martinez is mentioned in the quest Find out what happened to Gomez, in which it's claimed that Gomez was last seen having an argument with Martinez before he mysteriously went missing.
In the quest Help Pablo atone for his sins, if the player tells Martinez that Pablo is looking to return to society, Pablo will go missing a few days later - supposedly the work of "El Diablo".
Martinez can teach the player of the history behind Santa Clara and the tale of El Diablo.
Martinez is named after Maximiliano Hernández Martínez, President of El Salvador from 1931 to 1944. Martínez was feared for his oppressive fascist regime, in which he would have any and all opposition murdered.
If Martinez is killed before beginning the Santa Clara quest arc, all subsequent Santa Clara quests will automatically fail.