Body or body part

1x15 Disco Inferno  Directed by James Whitmore Jr.
 Written by Tyler Bensinger
 First Air Date : Sunday, 22 February 2004
 Flashback year : 1978 (26 years ago)
 Film tribute : Saturday Night Fever
 Based on real case : The Station nightclub fire

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.

We don't got a cold one here. We got 23 of them.

1x16 Volunteers  Directed by Allison Anders
 Written by Jan Oxenberg
 First Air Date : Sunday, 7 March 2004
 Flashback year : 1969 (35 years ago)
   

When the remains of a young black man and a white woman are found under the foundation of a building, Rush and Valens discover that not only did the two go missing in 1969, but that they may have been killed professionally for their work in an underground abortion clinic.

2x04 The House  Directed by Alex Zakrzewski
 Written by Sean Whitesell
 First Air Date : Sunday, 24 October 2004
 Flashback year : 1968 (36 years ago)
   

When human remains are found outside a former state prison, the team re-opens the 1968 case of a dead inmate, murdered on the night Johnny Cash's Folsom Prison Concert was broadcast to prisons throughout the country. However, when it's revealed that the bones don't belong to the person everyone had assumed, the team must start the probe anew by first identifying who the victim was.

2x09 Mind Hunters  Directed by Kevin Bray
 Written by Veena Cabreros Sud
 First Air Date : Sunday, 28 November 2004
 Flashback year : 1985 (19 years ago)
   Based on real case : Robert Hansen

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.

2x22 Best Friends  Directed by Mark Pellington
 Written by Liz Garcia
 First Air Date : Sunday, 8 May 2005
 Flashback year : 1932 (73 years ago)
   

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.

I came up from the dark without you, and every day since has been in shadow.

2x23 The Woods  Directed by Nelson McCormick
 Written by Veena Cabreros Sud
 First Air Date : Sunday, 22 May 2005
 Flashback year : 1972 (33 years ago)
   

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.

It's darkness. It always comes back.

3x05 Committed  Directed by Alex Zakrzewski
 Written by Liz Garcia
 First Air Date : Sunday, 23 October 2005
 Flashback year : 1954 (51 years ago)
 Film tribute : One Flew Over the Cuckoo’s Nest
 

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.

- It was my decision as a medical professional.
- To lobotomize Bettie?
- You have to understand. At the time we thought it was the cure.

3x09 A Perfect Day  Directed by Roxann Dawson
 Written by Veena Cabreros Sud
 First Air Date : Sunday, 27 November 2005
 Flashback year : 1965 (40 years ago)
   

When a fisherman finds evidence of a young girl's death washed up on a shore in New Jersey, Lilly re-opens the 1965 case of 4-year-old child who had a seemingly abusive mother.

4x02 War at Home  Directed by Alex Zakrzewski
 Written by Samantha Howard Corbin
 First Air Date : Sunday, 1 October 2006
 Flashback year : 2004 (2 years ago)
   

The team re-opens the 2004 case of a female veteran of the Iraqi War when her prosthetic arm is found in a river. Meanwhile, Scotty visits his older brother in connection with a case that brings up painful memories from their childhood.

4x03 Sandhogs  Directed by David Von Ancken
 Written by Greg Plageman
 First Air Date : Sunday, 8 October 2006
 Flashback year : 1948 (58 years ago)
   

When the remains of a sandhog miner who disappeared in 1947 are found in a subway service tunnel, the team is prompted to re-open the case when they suspect the victim might have been murdered for being a union activist.