You can download the official rules for Mastermind (the classic game, which is functionally identical to most “Operation Mastermind” editions) for free from several reputable sources:
: The investigation reveals that the murder is inexplicably linked to a series of critical computer malfunctions. Carstairs must unravel a web of mystery to find the connection between the dead magician and the technological chaos. Educational & Reference Context operation mastermind pdf free download