Jubilation sweeps planet earth after First Contact with extraterrestrials, the friendly and technologically advanced Djbrr—aliens with an attitude who love to party. Then catastrophe strikes earth’s greatest technological achievement, Grissom Base on Jupiter’s moon Io, and humanity faces a crisis of confidence. Earth’s top physicist responds, creating Excelsior, the craft he believes will travel faster than light, an achievement the Djbrr—like Albert Einstein—think is impossible. But the suspicious death of an Excelsior crewmember and an unknown scientist’s warning of hidden danger lurking behind the light barrier raise the question— Which is faster, the speed of light, or the speed of darkness?