In 2004, Ashley was kidnapped by Jack Krauser, a mercenary working for Osmund Saddler of Los Iluminados, while coming back home from her college in Massachusetts. She is taken to a remote village somewhere in Spain, where she is apparently held for ransom by Los Iluminados.
After receiving intelligence about Ashley's whereabouts, the U.S. Government sends agent Leon to investigate the area. He discovers that the local villagers are actually members of Los Iluminados, converted to their beliefs through parasitic organisms known as Plaga. Leon discovered Ashley in a church on the outskirts of the village. Shortly afterwards, the two met with the cult leader, Saddler, who revealed that Ashley (as well as Leon) was administered with one of the Plaga parasites, and that Saddler was planning to return Ashley to the President in order to infiltrate and destroy the U.S. Government from within.
After escaping Saddler and the villagers, the two found their way into Ramon Salazar's castle, and later, into Saddler's island complex. Ashley would repeatedly be recaptured by Los Iluminados during Leon's mission and subsequently rescued each time. Within the island complex, the two found a laser surgery machine built by Luis Sera with the purpose of removing a Plaga internally from its host's body. Leon and Ashley used the machine on themselves, destroying their Plaga parasites and thus, removing Saddler's only leverage on them.
After Saddler was eliminated, Leon and Ashley made their escape from the collapsing island on a jet ski left by Ada Wong. Ashley offered Leon to come over to her place for "some overtime", which Leon politely declined. Afterwards, the both of them were picked up by American authorities.