November 2009, Boston. For the past three months, Agent Harry Ethan Rhodes had been chasing a ghost at his desk in the FBI's Boston field office. Four men had been murdered within the state's borders, with no geographical or social ties to each other. There were no fingerprints, no DNA traces of the killer. The inadequate digital databases of 2009 and the city's grainy, low-quality street cameras weren't helping Rhodes. But Rhodes wasn't an ordinary detective. His expertise in behavioral analysis, combined with his intelligence, led him to notice a detail hidden in the dusty archive files of the victims: all the murdered men were monsters who had been convicted of serious crimes such as rape, child abuse, or femicide, but had somehow managed to slip past behind bars through technical loopholes or bribery. This wasn't an ordinary serial killer. This was a relentless hunter filling the gaps in justice. That bleak autumn evening, the rain poured down, holding the streets of Boston captive. Rhodes was walking home down a deserted street, trying to unravel the complex knots of the case in his mind. He had pulled up the collar of his overcoat and quickened his pace when a sound rising from the depths of the street pierced the silence like a knife. The deathly, agonizing scream of a man on his deathbed… Rhodes’ reflexes kicked in less than a second. His right hand quickly went under his overcoat, and he drew his official Glock pistol from his belt and released the safety. His pulse pounding, he tiptoed towards the sound, toward the darkest corner of the street. In the middle of the darkness, under the faint light of a single street lamp, he saw the silhouette. A hooded figure, his face masked, dressed entirely in black, stood over the body lying on the ground. He was no more than 1.60 meters tall. The light from the street lamp illuminated the silhouette's outline. Rhodes looked carefully; those shoulders, that thin build couldn't belong to a man. She looked so delicate, more like a young girl than an adult woman. Rhodes was about to yell,

when the silhouette quickly turned its head towards him. The eyes beneath the mask met Rhodes's for a moment. Instead of lunging at him to attack or surrender, the girl turned around in a split second and ran towards a black, ferocious machine waiting at the street corner: a 2008 Honda CBR 1000RR. The girl jumped onto the motorcycle like an acrobat. The moment she pressed the starter, the high-revving, high-pitched, wild roar of the four-cylinder beast echoed off the walls of the deserted street. As soon as she released the clutch, the rear wheel gripped the wet asphalt, splashing water, and the girl vanished into the darkness, leaving only exhaust fumes and raindrops behind. Rhodes stood there, gun in hand, in the middle of the wet asphalt. Even if he chased after her, catching the beast was impossible. As he approached the victim lying in a pool of blood on the ground, he murmured,