Every action has an equal and opposite reaction.

Rhea Strathmore creates death. Locked within her laboratory at The Arsenal, she concocts whatever's necessary to protect those around her. She won't ever negate her pre-Arsenal deficit, but she'll try. Her past work now threatens everyone she cares for and exposes secrets she's kept buried. The mysterious man tasked with keeping her alive is more lethal than anything she's ever concocted.

Everything has a price.

Fallon Graves defies death with every assignment. He may have traded in his lone operative lifestyle for The Arsenal, but that doesn't mean he's a team player. He's survived his entire life with no one. Why should he change? When Rhea's past threatens The Arsenal, Fallon is forced to question everything he's valued. She's a liability in the field, but he's not about to let anyone harm the woman who's more dangerous than any explosive he's ever created.

Together, Rhea and Fallon are one volatile chemical reaction away from going up in flames.