A routine traffic accident, resulting in the death of one Martin Valada, has Barry Allen investigating the case as a crime. Despite the efforts of the assistant chief of detectives, John Hinchman, to dismiss Allen's notion, Allen continues his investigation. A man named Norville White reaches out to Allen for assistance, but by the time Allen can make contact, White has been murdered by Dark Matter. Allen, as the Flash, squares off against Dark Matter, but is subdued. Hinchman lays Allen off the police force, but Allen continues with his investigation. Dark Matter's next victim is an elderly woman, named Elizabeth Chen. Searching for clues at Chen's apartment, Allen, as the Flash, is asked, by HInchman, at gunpoint, to leave the scene of the crime. An unexpected break in the case comes in the form of one of the Flash's Rogue's Gallery, Captain Cold. The frosty felon was acquainted with Chen, and points the Flash at Lannister Labs. The Flash has his second encounter with Dark Matter at Lannister Labs. Unfortunately, investigative reporter Iris West is also on the scene, and suffers great injuries at the hands of Dark Matter. Allen has maintained a vigil at West's hospital bedside, ever since.
West awakens and explains her presence at Lannister Labs. She had tried to help Allen after Hinchman laid him off. Delving into Hinchman's phone records turned up several calls to Curfew Cosmetics. Another source revealed that Hinchman had been asking for directions to Lannister Labs, ostensibly to purchase property nearby. West was aware that both Valada and Chen had worked at a lab, though had never heard of Lannister Labs. Allen reveals to West that Dark Matter's murderous motivations seemed to revolve around the death of his parents. West suddenly remembers that John Paul Curfew, the head of Curfew Cosmetics, also lost his parents, at a very early age. Allen leaves West's bedside to mull over the case. As he wanders the streets of Central City, he becomes aware that he is being followed. Allen easily slips the tail by moving at superhuman speed. Allen enlists the aid of a trusted police officer to watch over West during her hospital stay. Allen reaches out to a friend at the phone company to collect the phone records of several relevant persons to the investigation. While he waits for the information, a police bulletin comes in over the radio, tipping Allen off to a crime, in progress, being perpetrated by the Trickster. Allen, as the Flash, races over to the scene of the crime. Despite the Trickster momentarily blinding the Flash with a powerful strobe, the Flash quickly takes down his old foe, and returns to his previous investigation.
Returning to the prison to question Captian Cold further, Allen discovers that the villain has escaped his cell, using a miniature cold gun, embedded under his thumbnail. Receiving the phone records, Allen finds that Chen made a number of calls to White, and also a man named Otto Henderson, shortly after Valada's death. Hinchman learns that Allen slipped his tail, and that West is under police protection, at the hospital. Before the Flash can get to Henderson he is distracted by an armored car robbery being carried out by Captain Boomerang. The Australian rogue hurls several razor sharp boomerangs at the Flash, programmed to pursue him. The Flash conceals his costume under a hooded coat, which confuses the boomerang's tracking systems. The Flash destroys the boomerangs, then apprehends Captain Boomerang. The Flash reaches Henderson just as Dark Matter attacks. The Flash spirits Henderson to a safe locale, then returns to confront Dark Matter. The Flash captures Dark Matter in a super speed generated whirlwind. The sudden appearance of Captain Cold, however, distracts the Scarlet Speedster long enough for Dark Matter to clip him. To the Flash's surprise, Captain Cold attacks Dark Matter, prompting the Flash to rescue his old foe when Dark Matter retaliates. Using Captain Cold's gun to coat himself in an icy sheath, the Flash is able to resist Dark Matter's enormous fiery output long enough to defeat the murderous villain. Dark Matter, however, turns out not be Curfew, who Dark Matter actually murdered earlier that night, but Curfew's assistant, Frederick Fleming. Fearing that the murders would be pinned on him, Captain Cold had intervened to clear his name. With Fleming under arrest, Hinchman turns state's evidence against him, in return for a lighter sentence. Fleming's parents had been scientist in the employ of Lannister Labs. An accident while researching dark matter cost them both their lives, years after the incident. Though seemingly innocent of any wrongdoing, Fleming, nonetheless, held Chen, Valada, White, and Henderson accountable for their deaths, and sought vengeance. With the case closed, and Hinchman behind bars, Allen is re-instated on the police force.