Maurice is an uplifted Saurian similar to those found on Eden-6. As such, he is capable of speech (via a voice modulator) and intelligent thought. Despite this, Maurice still struggles with social etiquette and often makes comments that sound unintentionally threatening. However, Maurice also assures the Vault Hunters that he means no harm.
Maurice was invited to Sanctuary III by Tannis as part of a "cultural exchange" program. Unlike other Saurians, Maurice is not hostile as his only interest is to further scientific knowledge and cultural understanding. Maurice's origin is unknown, though he claims to be from a planet where "Saurians reign supreme and humanity has died away".
Upon downloading the Bloody Harvest update, Maurice can be found on the top deck of Sanctuary III, next to the Mayhem Mode console. After introducing himself, Maurice gives the player the Descent into Heck event quest. Maurice asks the player to find a ghost located within haunted enemies. He then tasks the Vault Hunters with killing ghosts and collecting the Hecktoplasm they drop.
Once enough Hecktoplasm has been collected, Maurice recalls the Vault Hunters to Sanctuary III. Upon arrival, Maurice explains the recent hauntings originate from Heck and are being led by Captain Haunt. He then uses the Hecktoplasm to power a machine that opens a portal to Heck and sends the Vault Hunters to kill Haunt.
After killing Haunt, Maurice will reward the Vault Hunters and offer a repeatable version of the Bloody Harvest quest. Between missions, Maurice will continue to wander around the Mayhem Mode console, occasionally making various comments.