Dark is a German science-fiction mystery thriller television series created by Baran bo Odar and Jantje Friese. It ran for three seasons from 2017 to 2020. The story primarily follows four families from the fictional town of Winden, Germany, as they pursue the truth in the aftermath of a child's disappearance, unraveling a sinister time travel conspiracy that spans several generations. The series explores the existential implications of time and its effect on human nature and life, with its plot structure making prominent use of the bootstrap paradox. It features a large ensemble cast led by Louis Hofmann. Dark debuted on 1 December 2017 on Netflix; it is the service's first German-language original series. The second season was released on 21 June 2019, while the third and final season was released on 27 June 2020. Dark has received critical acclaim for its performances, casting, direction, writing, tone, visuals, themes, musical score, and the ambition and complexity of its narrative structure. It has been nominated for and won several awards. In 2021, the BBC ranked the series as the 58th greatest TV series of the 21st century.