"Unknown" is a detective series about a man with a phenomenal memory who has lost his memories of his own identity and life. Not knowing who he is, the lost hero takes on a random surname - Shagin - and becomes a consultant for the special investigative group of the Bureau, consisting of three employees under the leadership of Evgeniya Pichugina. Processing massive streams of information with astonishing speed, the nameless newcomer helps the team solve unusual cases.