Season 4

1. Pure Evil

2012-09-09

The 1995 death of a Chicago woman whose body was found on a Wisconsin highway is detailed in the Season 4 premiere.

2. The Perfect Suspect

2012-09-16

In Arkansas, three women are murdered over the course of three years.

3. Wolf in Sheep's Clothing

2012-09-23

The 1995 murder of an 8-year-old girl sparks a manhunt for her killer.

4. Blood Trail

2012-09-30

The 1999 slaying of a young woman in Germantown, Wis., is recalled.

5. Mother's Day Murders

2012-10-07

The 1985 murders of a young military wife and two of her daughters are investigated.

6. Gruesome Discovery

2012-10-14

Recalling the 1994 murder case of a young mother who was beaten and left in a garbage bin.

7. A Bike Ride to Murder

2012-10-21

The 1991 murder of a young girl in San Diego is investigated.

8. Murder on the Menu

2012-10-28

The 2004 murder and dismemberment of a chef is investigated.

9. Triple Threat

2012-11-11

The 1993 strangling death of a young mother in California is probed.

10. City Under Siege

2012-11-18

A look at the 2006 shooting death of a young nightclub worker in Scottsdale, Ariz.

11. Killings in Kentucky

2012-11-25

A 1993 triple homicide results in the deaths of a Kentucky veterinarian and his family.

12. No Mercy

2012-12-02

The 2001 strangling death of a mother of triplets in Puyallup, Wash., is investigated.

13. Maritime Murder

2012-12-09

The 1982 poisoning death of a naval officer is investigated.