Alex Mercer, also known by her Blackwatch codename Zeus, was the former head researcher of the Blacklight Project at Gentek. After learning that those affiliated with the project were being systematically murdered, Mercer attempted to flee the city with a sample of her research contained in a vial. Cornered at Pennsylvania Station, Mercer smashed the vial and unleashed the deadly virus into the surroundings. This triggered a viral outbreak that eventually covered all of Manhattan Island.

Alex Mercer, also known by her Blackwatch codename Zeus, was the former head researcher of the Blacklight Project at Gentek. After learning that those affiliated with the project were being systematically murdered, Mercer attempted to flee the city with a sample of her research contained in a vial. Cornered at Pennsylvania Station, Mercer smashed the vial and unleashed the deadly virus into the surroundings. This triggered a viral outbreak that eventually covered all of Manhattan Island.