These charges sound like the movies, but the reality is usually messier. A custody dispute where one parent took the kids. A heated argument where someone grabbed another person and moved them across a room. A demand for money during a breakup that the other side now calls a threat.
Kidnapping under California law turns on movement of another person by force or fear, and the distance and circumstances drive the exposure. Aggravated kidnapping, where the movement is tied to a ransom, a robbery, or a sexual offense, can be punished by life in prison. Extortion, obtaining money or property through a wrongful threat, is its own felony with its own state-prison exposure. The gap between a frightening situation and a life-altering charge is often a question of legal definition, not just what happened.
I prosecuted serious and violent felonies for the Stanislaus County DA, including cases carrying life exposure.
Whatever you do, don't try to talk your way out of it with detectives. Ask for a lawyer and say nothing else.