THE SHADOW FREQUENCY

You cannot run from a weapon you cannot hear.When the untouchable kingpins of Dhaka's brutal underworld start dropping dead inside their fortified penthouses, the police are baffled. There are no bullets, no forced entries, and no fingerprints. The only clue is a shattered window and a silent, untraceable frequency.Senior Inspector Khalid Chowdhury is a veteran detective who believes in the absolute rule of law. But his investigation leads him to an impossible adversary: Farhan Zaman, a brilliant nano-acoustics engineer pushed beyond the breaking point by the murder of his sister. Armed with a custom-built stealth drone and a devastating 18.9 Hz infrasound weapon, Farhan is bypassing the corrupt judicial system to balance the ledger in blood.As the invisible drone circles the city's ultimate crime boss, Khalid must race against time to stop a man who has turned science into an inescapable executioner. The Shadow Frequency is a heart-pounding techno-thriller where justice and vengeance collide in the dark.