 The differences become drastically more pronounced after 1996, when a deadly virus kills hundreds of millions in the Prime world.The virus is suspected of being purposefully delivered from the Alpha world, resulting in a tense Cold War state between the two worlds, with counterparts used as spies and sleeper agents.Silk's Alpha world continues to resemble ours, but the Prime world becomes quite different, with Howard Silk Prime being a ruthless and cold intelligence operator.