Final answer:
The serial killer who kept the heads of his victims in a freezer was Jeffrey Dahmer.
Step-by-step explanation:
The serial killer who kept the heads of his victims in a freezer was Jeffrey Dahmer. Dahmer was an American serial killer and sex offender who killed 17 men and boys between 1978 and 1991. After murdering his victims, Dahmer dismembered their bodies and kept some of the body parts, including the heads, in his apartment.