The Mansion Incident is the name given to a biological, ecological, and environmental disaster which took place in and around Umbrella's Arklay Laboratory in the Arklay Mountains northwest of Raccoon City. The Arklay Laboratory, constructed in the 1960s, was used by the Umbrella Corporation for viral research. Officially, this was the site of vaccine research for RNA viruses such as Ebola. Unofficially, it was also the site of bio-weapons research for military application.[1] The disaster was influenced by a sentient organism known as Queen Leech, which triggered the containment failure of a variant of the dangerous t-Virus. The disaster officially concluded with a S.T.A.R.S. investigation two months later, resulting in both the exposure of Umbrella spy Dr. Albert Wesker within the unit, and the destruction of the laboratory.


On May 11, 1998 the Queen Leech triggered a containment failure in the underground laboratory. This was detected soon after, and all employees at the grounds regardless of duties were ordered to wear protective-pressure suits to protect them from exposure to the t-Virus.[2][3] In order to limit the spread information, Dr. Albert Wesker - a member of one of Umbrella's security organizations - ordered that no one be allowed access to the complex's telephones.[4] The security guards were then given orders to shoot anyone trying to leave the facility, a precaution should the staff be infected.

By May 13 people began showing signs of t-Virus infection, the Queen Leech's sabotage having gone completely unnoticed. Possibly in an effort to prevent panic, the medical team only provided bandages to those displaying decomposition rather than provide antiviral medication.[2] Work on a vaccine is known to have been underway at some point, based on the S.T.A.R.S. findings.[note 1]

Over the next few days, however, the psychology of the residents did change. The animal keeper is a good source for the changes which took place in the first two weeks. He recorded in his diary, dated May 14, his apathy towards a pack of infected dogs ripping through their cages and escaping into the forest. The keeper also noted a man trying to escape from the facility and being killed.[2] Over the next few days his mental state deteriorated, with an increasing appetite. After eating dog food, he murdered and partially ate his friend, Scott on May 21.[2] Another source, Martin Cluckholm, committed suicide on June 3; by this point many of the mansion's employees had transformed into Zombies, and he believed himself to be the only one left.[4]

Mountain deaths

Almost immediately after the infected dogs escaped the mansion on May 14, they began attacking and killing hikers and residents in the outskirts of the city. Seven hikers and mountain climbers from out-of-town were found dead. Of these seven confirmed deaths, five were found alone and two pairs were found together after the attacks. Another thirteen local people from four households were killed by a combination of animal attacks and Zombies,[5] with some being attacked in their homes.[6] Following these deaths, all roads into the Arklay Mountains were closed off by the police on Thursday, July 9.[citation needed]

S.T.A.R.S. investigation

Following continuing pressure from the local population, the Raccoon City Police Department assigned S.T.A.R.S. the mission of flying into the mountains and searching an area suspected of being the killers' den. Umbrella sent a fax to their agent and former head of security, S.T.A.R.S. Alpha Team Captain Albert Wesker, ordering him to sabotage S.T.A.R.S.' chances of escape and record their fighting with the B.O.W.s to estimate their success in combat. On July 23, the S.T.A.R.S. Bravo Team's helicopter was forced to crash land due to an engine failure.

Around the same time, the Ecliptic Express train had also became infected with the t-Virus via Marcus' leeches, screeching to a halt. Rebecca Chambers, a member of Bravo Team, decided to investigate the train. Likewise, Bravo Team's primary pilot, Kevin Dooley, was killed by the escaped Cerberus pack, whereas the co-pilot, Edward Dewey, managed to survive the attack, but soon succumbed to his wounds upon entering the Eclipse Express, though not before warning Rebecca Chambers that there were zombies and monsters in the forest.

Wesker, alongside researcher William Birkin, observed the events, and also gave commands to the Umbrella investigative squad on the train until they met their own ends at the hands of Marcus' leeches and were promptly infected.

Bravo Team eventually managed to arrive at the Spencer Mansion, while Chambers arriving at the Umbrella Research Center with an escaped convict, Billy Coen. Wesker and Birkin were also surprised by Marcus' apparent revival, with Wesker departing to take care of the escaped prototype tyrant, leaving Birkin to activate a Gondola.

The next day, these events also forced them to activate the training facility's self-destruct protocol, to which Wesker also decided to leave Umbrella. Wesker also had to contend with an Ivan dispatched by Sergei for his disobedience, although the self-destruct devices activating allowed Wesker an opportunity to escape when Sergei and the Ivan were forced to block the explosions, also retrieving the T-A.L.O.S., an event which Rebecca and Richard Aiken briefly witnessed before being attacked by the Yawn B.O.W.

Likewise, Wesker himself led Alpha Team to search for the missing members of Bravo Team, and were then forced to hide out at the Arklay Mansion after the discovery of the Bravo Team's crashed helicopter ended in an ambush by Zombie Dogs that resulted in the death of Joseph Frost. Wesker then had Barry Burton lure the rest of his team into various traps, under the threat that Wesker kill his family if he doesn't do so.

Alpha Team members Chris Redfield and Jill Valentine later discover Enrico Marini in the caverns of the mansion, and reveals that he found some evidence of a traitor within the unit, citing that he managed to draw it down to two suspects, Wesker and Redfield. However, he is then gunned down by an unknown assailant (actually Wesker) and killed, although not before he hints that Umbrella was responsible for the disaster in his dying breaths.

Wesker then planned to obtain combat data of the Tyrant for himself, also injecting himself with a prototype virus, having anticipated the possibility that the Tyrant would murder him when he released it. They later find the laboratory and find Wesker among the photos, causing them to learn that Wesker was in fact the traitor to the unit. Wesker then ordered the Tyrant kill them, but as he had anticipated, the Tyrant turned against him and impaled him before going after them.

Jill and Chris later wound the Tyrant and seemingly killed it, although it was revived shortly thereafter. Likewise, the prototype virus also allowed Wesker to survive the Tyrant's earlier attack, also imbuing him with superhuman abilities at the cost of his humanity.

Jill; Chris; Barry and Rebecca all escape after killing the Tyrant once and for all, as well as set the self-destruct device, with Barry Burton also aiding in the escape effort. Wesker, meanwhile, also escaped, and had run a mile away from the mansion before the self-destruct device went off, also killing Lisa for good in the process.


Main article: Queen Leech
James Marcus

The Queen Leech.

The Queen Leech was a sentient leech which had absorbed the memories of Dr. James Marcus following his 1988 assassination. Believing itself to be Marcus, it took the appearance of his younger self and began a series of attacks on facilities run by Umbrella. The Leech was killed by 2LT Billy Coen and S.T.A.R.S. officer Rebecca Chambers before it could do more damage.


The laboratory's explosion caused a large forest fire which destroyed an area of forest equal to 750 acres (304 ha; 1.172 sq mi). The Raccoon Fire Department found itself under-equipped and the National Guard was brought in to assist.[7]

Following their return, S.T.A.R.S. called for an immediate investigation into Umbrella's affairs, but the unit was disbanded owing to Umbrella's financial influence over the Chief of Police, Brian Irons.[citation needed] While the public at large became aware of the incident and the Umbrella connection, little was said. The Raccoon City Police Department later started an investigation in August, though Umbrella was given the advanced warning by Chief Irons and knew to hide evidence in preparation for it.[citation needed]

Umbrella's own investigation into the incident resulted in the forced resignation of Morpheus D. Duvall for "gross negligence", the corporation using him as a scapegoat. Duvall would later form a terrorist organization and attack Umbrella in 2002.[citation needed]



  1. Trays of eggs can be found in the laboratory in the 2002 remake. Eggs are used for vaccine synthesis.
  1. Wesker's Report II
  2. 2.0 2.1 2.2 2.3 Resident Evil (2002), file: "Keeper's Diary".
  3. Hamamura (ed.), KAITAISHINSHO, p.234.
  4. 4.0 4.1 Resident Evil (2002), file: "Researcher's Will"
  5. Inside of BIO-HAZARD, p.121.
  6. Resident Evil (2002), scene: Opening.
  7. Takeo (ed.), Inside BIO-HAZARD, p.121.
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