While the original "Resident Evil" (1996) was still in development, the idea for a prequel came up shortly after the 64DD peripheral for the Nintendo 64 was announced in 1995. The 64DD's low sales four years later eventually made Capcom decide to develop "Resident Evil Zero" as a cartridge-based Nintendo 64 release. Capcom started development on the Nintendo 64 version shortly before the summer of 1998, one of many "Resident Evil" games being developed at the time. One of these was "" (2000) which was taking full advantage of the capacities of the GD-ROM format. The Nintendo 64 cartridge could only store 64MB of data, one tenth that of a traditional CD-ROM. For these reasons, the team approached "Resident Evil Zero" with different ideas for gameplay and visual design that would function better with less storage space. After the script had been completed in early 1999, the production of a "Resident Evil" game for Nintendo 64 was revealed to the public by Yoshiki Okamoto, the president of Capcom's screenplay company Flagship.