Hunters
I've just started watching Hunters season one on Amazon Prime. It's set in the 1970s and is about a disparate group people seeking out infamous Nazis who are sheltering in the USA under assumed names and changed identities.
The first episode begins with a young lad living with his grandmother being murdered in their home by an unknown assailant. He was woken up by people talking but before he could get down to see what was happening, he saw the assailant stab his grandmother to death but not before he heard her say "You won't get away with it". It transpires later in the programme that his grandmother was a prisoner in Auschwitz, something she had kept from him and that covertly, she was a part of the Nazi Hunter group.
Alongside this, there is another thread in the story about a neo-Nazi group rising to power in US political circles and still intent on killing Jews, hiring a ruthless fanatical killer to do so.
A bit here if I've whetted your appetite.
https://www.imdb.com/title/tt7456722/