DARK is a sci-fi/mystery/soap from Netflix

Dark is a German science fiction thriller television series co-created by Baran bo Odar and Jantje Friese. It ran for three seasons from 2017 to 2020. The story follows characters from the fictional town of Winden, Germany, as they pursue the truth in the aftermath of a child's disappearance.Wikipedia

With a large cast (plus time travel) you may need help to keep track.
Netflix has a web site to help    (You need to Login or Register to view media files and links)

 
trailer
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Some of the boys... 

Daan Lennard Liebrenz ... Mikkel Nielsen
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Vico Mücke ... Yasin Friese
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Valentin Oppermann ... Mads Nielsen
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Tom Philipp ... Helge Doppler
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Joshio Marlon ... Tronte Nielsen
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Claude Heinrich ... Young Unknown
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?? ... Hanno
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Jonas Emilian Gerzabek ... Child Jonas Kahnwald 
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Poor Helge. 

No only does he get sent in the experimental time machine
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Not only does he get beat up
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But there is this one time .... he dawdles walking home from school, gets his uniform
all dirty, so his mom sets out to punish him.  She orders him to take off his clothes.
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(authentic 1953 boy underwear)
At this point his father arrives home, so Helge escapes the rest of the punishment.
This time.