When a mysterious alien woman from the planet Laertes convinces Dr Bashir to gamble for her at Quark's gaming tables, things seem innocent enough. Yet the more Dr Bashir wins, the more things go wrong in the Federation: ore ships vanish, planets lose their atmosphere, suns go nova. The cause and effect is hard to understand, but is proven by the bizarre Laertian science called Complexity Theory.
When Bashir tries to stop gambling, a Laertian warfleet appears to force him to continue, while on the planet Laertes itself Major Kira and Science Officer Dax must battle their way through chaos and danger to find a way to stop the Laertians - and save Deep Space Nine and the federation from utter destruction.