He may have died in Season 3, but Dacre Montgomery's Billy Hargrove made a surprise cameo in "Stranger Things 4" this week. A cameo that was reallllly tricky to pull off. The actor appeared in the season's fourth episode, as his sister Max (Sadie Sink) visited Billy's grave in the Hawkins cemetery. Once there, this season's Big Bad, Vecna, pulls her into a trance a trance in which she sees her dead, mangled brother, who chases her through the graveyard. But Montgomery and Sink never filmed together, both the actor and episode director Shawn Levy confirmed. Over the weekend, the "Power Rangers" star shared a ton of photos from filming in his hometown of Perth, Australia where he was filmed by a local crew while being directed over Zoom by Levy. "Feeling extremely fortunate to have been able to shoot these scenes during the pandemic in my hometown, Perth (in Australia)," he captioned pictures of him getting all bloodied up in the make