The Lone Wanderer lived in Vault 101 without incident for nineteen years, but in 2277, 200 years after the Great War, James disappeared without any explanation. The young Lone Wanderer, with the help of Amata Almodovar, left the safety of the Vault to look for James in the ruins of Washington, D.C. In order to find him, the Lone Wanderer travelled across the wasteland following James's trail, searching for clues and speaking to the people he encountered to find out where he went. After finding him, Project Purity was put back on track, but the reunion was cut short when the Enclave commander Augustus Autumn arrived and demanded ownership of the Project. James was unwilling to allow the project to fall into the hands of the Enclave and sacrificed himself by filling the control chamber of Project Purity with deadly amounts of radiation, in hopes to kill Colonel Autumn and the other soldiers. Colonel Autumn, however, survived. The Enclave took control of the project, but were unable to operate it.
After fleeing from the Jefferson Memorial building with the remainder of Project Purity staff, The Lone Wanderer took refuge within the Citadel and enlisted the help of the Brotherhood of Steel to retrieve a G.E.C.K. from Vault 87 for use in a soon-to-be-recaptured Project Purity. Because the G.E.C.K. is in a highly irradiated chamber, the Lone Wanderer must then choose whether to enlist the help of Fawkes, a friendly super mutant, or face the deadly amounts of radiation alone. Once the G.E.C.K. was retrieved, the Lone Wanderer was captured by Colonel Autumn and taken to Raven Rock. There, President Eden presented the Wanderer with a canister of modified FEV for insertion into Project Purity, which would poison any mutated creature drinking the purified water. It is unknown whether the Wanderer obeyed this instruction, but it is known that Raven Rock was destroyed and Project Purity, recaptured with the aid of Liberty Prime. There, after finally stopping Colonel Autumn, the Wanderer and Sentinel Lyons were faced with the dilemma of who would enter the radiation-flooded chamber and activate the project. Once the purifier was activated the wasteland is finally given the greatest gift of all: fresh, clean drinking water.
The Lone Wanderer awakens two weeks later to face the consequences of their decisions so far and joins the Brotherhood as a knight, in their mission to distribute the newly-purified water and to hunt the Enclave remnants. This hunt would eventually put the Wanderer in control of an orbital strike. The Lone Wanderer either uses it to destroy the Citadel or the Enclave Mobile Base Crawler. During or after the events of Fallout 3, the Lone Wanderer travels to various places such as The Pitt, Point Lookout, Mothership Zeta and participates in a simulation of the Anchorage Reclamation.
The Lone Wanderer is named "Albert" in Fallout 3 previews. This may be a reference to Albert Cole, one of the possible identities of the Vault Dweller.
The Lone Wanderer is shown in promotional images as being a Caucasian male with brown hair, which is the first pre-made appearance in the character creation phase at the start of the game.
The Lone Wanderer does not have any stated relation with the protagonists of the other Fallout games.
July 13, 2258, the birthday of the Lone Wanderer, is a Tuesday.
Their name is somewhat ironic. Though they are called the Lone Wanderer, they are the only player character thus far to be seen with a companion in the final cut scene unlike Fallout, Fallout 2, or Fallout: New Vegas.