Oslo, 2018. Former long-distance runner Sonja Nordstrøm never shows at the launch of her controversial autobiography, Always Number One. When celebrity blogger Emma Ramm visits Nordstrøm's home later that day, she finds the door unlocked and signs of a struggle inside. A bib with the number "one" has been pinned to the TV. Police officer Alexander Blix is appointed to head up the missing-persons investigation, but he still bears the emotional scars of a hostage situation 19 years earlier, when he killed the father of a five-year-old girl. Traces of Nordstrøm soon show up at different locations, but the appearance of the clues appear to be carefully calculated—evidence of a bigger picture that he's just not seeing. Blix and Ramm soon join forces, determined to find and stop a merciless killer with a flare for the dramatic, and thirst for attention. The trouble is, he's just got his first taste of it.