Each episode of Cold Case follows a formula that begins with a flashback scene that establishes the year -- sometimes the actual date -- in which the crime took place, as well as a set of characters in a seemingly mundane situation. These flashbacks feature a different style of direction, whether it be the colors, lighting, shading, or camera angles. Flashbacks often match a style from that era, such as a black-and-white flashback depicting the 1950s. The next scene shows the corpse of the victim--usually one of those introduced earlier--as it was discovered at time or sometime later after having first been declared missing. With some exceptions however there is no corpse but indications of a violent act in which the victim is missing without any trace.
The show then flashes to the present day, with the detectives of the homicide division of the Philadelphia police department prompted to reinvestigate an old case gone cold following, for example, a revelation of new evidence, discovery of the victim's physical remains, or a witness who has decided to come forward. The detectives then give the cold case a new look and begin researching the victim and interviewing their friends, acquaintances, and family.