What is the better way for let the game control the player from time to time

Good afternoon, On the game I am working on, there are moments where the player have to wait for a NPC to accomplish an action or, sometimes, the player doesn't have the control of his character (like a sort of cinematic sequence). What I would like to do is : should I use a state machine to tell my game controller when to be in charge of the player character or should I use an event manager ? I hope I was clear enough but I am very French, Regards,