The very first scene

Indeed, watch - or read - carefully. Le Carre has purposely crafted this story in a series of nested realities - a man now writing a memoir about then for his son to read in the future, for instance - in order to capture the hall-of-mirrors quality of the "secret world," as he calls it. Yes, the story jumps forward and backward many times, but watch/listen carefully and you'll find yourself in the hands of a true master of storytelling. Without question.