Tesseract

"Tyson's Folly, Manhattan's newest building, was a windowless cube, an impenetrable fortress dwarfed by the taller structures of midtown. Even preoccupied by the frightening news of escalating world tensions, people took the time to speculate about the purpose behind Tyson's Folly. But wealthy recluse Jonathan Tyson wasn't talking. Until Mark Johnson, a young executive in Tyson's financial empire, was summoned to Tyson's Folly, the first outsider ever to glimpse its interior. Deep inside the bizarre fortress, Mark learned of his new--and unusual--promotion and the impossible assignment he was expected to carry out. Somehow, he had to bring peace to one planet, and discord to another, to save two civilizations from destruction. His journey would span past and future and light-years of space. But he had Time itself on his side..."--Pg. [4] of cover.