At the beginning of Season 4, Joyce Byers receives a mysterious parcel, which turns out to be a Russian doll containing a ransom letter.
It was signed "Enzo," a reference to the restaurant Joyce and Hopper had a date at before the tragic events of season 3.
It was then revealed that "Enzo" is actually Dmitri Antonov, a Soviet prison guard who threatened Joyce with $40,000 in exchange for Hopper's return to America.
Throughout Stranger Things Season 4, his connection with Hopper evolves from guard-and-prisoner to a strong bromance fraught with survival worries.
Now, let's talk about who plays Enzo/Dmitri in Stranger Things Season 4?
Tom Wlaschiha, a German actor, was one of the numerous new faces to appear in Stranger Things Season 4.
You might recall the 48-year-old actor from Game of Thrones, where he plays faceless assassin Jaqen H'ghar, or Tom Clancy's Jack Ryan, an Amazon Prime original film.