New York, 1896. Police commissioner Theodore Roosevelt brings together criminal psychologist Dr. Laszlo Kreizler, newspaper illustrator John Moore and secretary Sara Howard to investigate several murders of male prostitutes.

Raised by her father, an ex-CIA agent, in the wilds of Finland, Hanna's upbringing has been geared to making her the perfect assassin. Sent into the world by her father on a mission, Hanna journeys across Europe, eluding agents dispatched after her by a ruthless intelligence operative. As she nears her ultimate target, Hanna faces startling revelations about her existence.

Oregon, 1851. Hermann Kermit Warm, a chemist and aspiring gold prospector, keeps a profitable secret that the Commodore wants to know, so he sends the Sisters brothers, two notorious assassins, to capture him on his way to California.

A professor and his students perform a dangerous experiment that causes a young woman to lose her sanity.

A man wakes up in the hospital with amnesia and struggles to find a connection with the life and family that is presented to him.