In this story of good and evil, good doesn't always win and evil isn't always clear-cut, forcing the characters to make difficult life-and-death decisions. Even though they're not a family in the traditional sense, the women form relationships that are just as powerful, often making sacrifices for each other. Girl power is strong in this story, but it's not overdone; when the girls work with other hunters, there's an equal give and take. The series posits that supernatural monsters and other dimensions exist and threaten humanity.
The heroines battle monsters of all different shapes and sizes, and the work is very violent. There are fistfights, weapons like guns, knives, flame throwers, and various items of their own making, and many scenes of peril for them and for innocent victims, including children. Dismemberment and torture are possibilities. Injuries look real, and some characters die.
"Damn," "hell," "s--t," and the like are audible.
This series is a sister to Supernatural, which involves the characters' backstories and histories with Sam and Dean.