Unlike more typical mansions, the Spencer Mansion did not conform to any particular set style, instead mimicking a variety of philosophies such as Regency and Second Empire. Albert Wesker was also reported to have survived the explosion, having become stronger using a prototype virus given to him by William Birkin. Alpha Team members Chris Redfield, Jill Valentine, Barry Burton, and Brad Vickers via helicopter before the detonation of the estate. Rebecca managed to escape the complex along with surviving S.T.A.R.S. Bravo team member Rebecca Chambers activated the self-destruct sequence.
The Mansion was later destroyed when surviving S.T.A.R.S. Bravo team division were killed by these B.O.Ws. This scheme had unfortunately proved to have had some success as much of S.T.A.R.S. would investigate the mansion as it was the center of the bizarre cannibalistic murders that took place in the suburbs of Raccoon City.
and at the same time, gain important combat data on the B.O.W.'s running loose in the mansion. Some of the Umbrella staff members (like the Chief of Security, or Albert Wesker) saw this as an opportunity to eliminate Raccoon City's law enforcement, S.T.A.R.S. James Marcus, was responsible for the t-Virus outbreak that ravaged the mansion as an act of revenge against Oswell Spencer for having him assassinated ten years earlier, thus beginning the events of the Mansion Incident. It was revealed that Queen Leech, posing as the "resurrected" Dr. Some who had yet to have fully succumb to the effects of the virus were killed either by suicide, by Umbrella's security team when trying to escape the mansion, or by the B.O.W's that had escaped their confinement. All inhabitants, which included Umbrella researchers, were infected from the virus and were (due to the viral nature) degraded into zombies. Thirty-one years later, there was an "accident" in the lab, and the latest strand of the t-Virus leaked, polluting the entire complex. George, who arrived later due to work commitments, was kept a prisoner on the grounds and forced into solving his own puzzles to escape, only to fall into a hole and die. Jessica and Lisa Trevor were immediately taken into captivity and subjected to human experimentation upon their arrival at the mansion. In November 1967, the Trevor family was invited over by Spencer to celebrate the mansion's completion, which he considered opening up as a hotel for employees at a pharmaceutical company he was making plans to establish, which became Umbrella Pharmaceuticals. Upon completion in 1967, Spencer commissioned a further construction project in secret, which saw the building of an underground facility in the caverns under the estate. The actual construction was met by a number of delays right from the beginning, with Spencer insisting the construction firm hired be replaced with one he could personally recommend. Trevor himself was well known for his convention-breaking designs, such as labyrinthine floorplans and elaborate traps and locking mechanisms.
By the start of that year he hired the New York-based architect George Trevor, likely of Trevor & Chamberlain. The wealthy British aristocrat Lord Spencer first envisioned an American mansion sometime before 1962.