the boy and his grandmother were. She drew a symbol on his hand and there was a symbol around the house, too. Everything was happening in the big house, and the main characters was investigating something. I also remember(don’t know from here whether) the man at the garage tie jammed and he died
This sounds very similar to an episode of The X Files –
Season 2, Episode 21 — ‘The Calusari’
https://www.imdb.com/title/tt0751222/?ref_=ttep_ep21
Full plot of the episode: https://en.wikipedia.org/wiki/The_Calusari