Kelly is an assassin, a trained killer and experimental chemist who specializes in poison. She's just turned fifty and has become weary of her lifestyle. Yet the assassin is in her blood - anger and cynicism prevent her from turning her back on killing for money. Especially now. After learning of the brutal rape and murder of her young charge, Sam, Kelly allows an inner rage to take hold and breaks protocol by torturing and killing one of the murderers, leaving his body for the rest of the gang to discover in their warehouse. But the gang is not about to vanish. They are dangerous - organized crime professionals who inhabit Europe's dark underworld - and now it's their turn to seek vengeance. Ignoring desperate phone calls from her superior, Ed, urging her to allow his agency to protect her, Kelly goes on the run and flees to Spain where she attempts to ride out the storm - without success.