The 1986 murder of a jockey is investigated after his body is discovered in a mass grave for horses. The victim disappeared shortly after losing a race that he had planned to be his finale before retiring.

Valens partners with Rush to locate her abducted, drug-addicted sister, while Jeffries tries to bring justice to the case of a murdered teenaged girl that has haunted him for 17 years.

The case of a female bank teller shot to death in her work in 2000 is reopened when the same bank is robbed again by perpetrators wearing identical masks and equipped with identical weapons as six years earlier.

The team re-investigates their oldest cold case yet, the 1919 murder of a young woman who was a passionate advocate for women's right to vote.

Rush tries to ignore her father's appeals to give her troublemaker sister another chance after she suddenly resurfaces.

Det. Stillman asks Lilly to re-open a case he couldn't solve, wherein an 8-year-old boy, Tim Barnes, was murdered in 1980. The prime suspects included a catholic priest, three glue-sniffing teenagers, one elusive suspect, and the boy's own parents.

The 1999 drowning death of a military academy's swim coach, which was originally ruled as accidental, is reinvestigated after the homicide division receives a note that suggests it was murder. Back at the office, Valens searches for Elisa after she goes missing.

When a poison-soaked towel turns up at the station, Lilly re-opens the 1973 case of a murdered female college tennis star.

The 1945 case of a murdered newspaper reporter is reopened when new evidence suggests that the woman was thrown in front of a passing train by someone she knew.

The headless torso of a woman who disappeared in 1985, on the same day she filed domestic-abuse charges against her husband, is found by hikers in a wildlife preserve. The investigation quickly leads to the grisly discovery of 8 more decapitated bodies, the victims of a serial killer.

When an old truck containing human bones is pulled from the Delaware River, the team re-opens the case of a missing and possibly murdered girl who disappeared unexpectedly in 1932.

The discovery of nine human skulls leads Rush (Kathryn Morris) back to George Marks, the serial killer she was unable to incriminate months earlier, and who walked away a free man. As the detectives reinvestigate his mother's murder from 1972, George is forced to emerge from hiding to face Rush again. This time, their very lives are at stake in their final showdown.

When a body is found in a dumpster, the team re-opens the 1984 case of a murdered teenage boy who wanted to become a dancer against his father's wishes.

The team suspect a 2004 arson that killed a psychiatrist may have been caused by her former patient.

Realizing that the missing Vera has finally hit rock bottom, his worried team members hope that a new twist to a 2006 arson case, which he was secretly obsessing about in recent weeks, might supply leads to his whereabouts.

When the son of a murdered high-school basketball star receives a death threat, Rush and Valens reopen the 1987 case of Herman Lester who was stabbed to death only hours after leading his team to win the state championship.

Lilly investigates an unsolved hit-and-run accident from New Year's Eve 1999 that left a man dead, after a recovering alcoholic comes forward and claims she is the one who hit him. But the evidence points to the guy being murdered, not accidentally run down.

Lilly reopens a 1990 murder case, in which a prep-school girl was found dead in a local swimming hole, after a present-day victim with similar markings is discovered at the same place. The investigation reveals that the victim of the earlier crime was routinely tormented by a trio of classmates who invited her to a sleepover the night she was killed.

The unsolved 1963 murder of a black teenager, whose body was discovered by the then-young Will Jeffries, is reopened.

In 1954, 9-year-old Otis Petrowski last saw his mother in a mental institution. Now over 50 years later, after the death of an elderly woman who had been using Otis' mother's identity, Det. Rush sets out to discover what happened to the boy's real mother.

The team re-opens the 1963 case of teenage girl who was then thought to have committed suicide. Now, new evidence leads them to believe the girl might have been murdered for acting and dressing like a boy.

The team re-investigates the suspected 2007 murder of a bride-to-be who was kidnapped on the day of her engagement party. Lilly and Scotty travel to West Virginia to escort the prime suspect to Philly, and on their way back, they hear his side of the story.

Rush and Valens investigate the case of a cold-blooded killer who shot a young man trying to hitchhike his way home to Philly from Atlanta.

Construction workers discover a skull with bullet hole under the ruins of a disco club burned down in 1978. 22 people died in the fire. Rush and Valens come to the conclusion that the burning of the club was arson, meant to cover up a murder leaving them with not one, but 23 cold cases.

Lilly and Valens reopen a presumed homicide from 1979 in which an unidentified victim's blood-drenched shoes, underwear and sheets were found in a trash bag, but no body. The investigation begins when a battered wife accuses her husband of murdering a girl in 1979 and brings in an amateur film from the time that supposedly shows him committing the crime.