Hell hath no fury like a Barb — back from Stranger Things' Upside-Down — scorned.

The fan-favorite character, whose fate seemed grim when she was lost to a shadowy dimension at the end of the Netflix show's first season, rose from the proverbial dead in a Tonight Show spoof that aired last night (August 31). And if you thought a Demogorgon was scary, wait until you see Barb pissed.

"What the f---!" Barb, played by Tonight Show head writer A.D. Miles, says after descending down the stairs and interrupting Mike's game of Dungeons and Dragons. "You forget about something? You forget about ol' Barb, Nancy's friend? Sitting on the diving board?"

The real cast of kids from Stranger Things — Millie Bobby Brown as Eleven, Finn Wolfhard as Mike, Caleb McLaughlin as Lucas and Gaten Matarazzo (who sometimes wears fake teeth, TMZ learned!) as Dustin — try to defend why rescuers might left her behind, yet managed to rescue Will. Maybe it was was too dark to spot her, they suppose, but Barb's not ready to forgive and forget.

"I don't have a distinctive look!" she mocks. "I don't have bright red Ronald McDonald hair, old granny glasses and a librarian's blouse!"

And while Barb may have been beaten down, it's she who gets the last laugh. Miles' version of Barb says she earned her freedom from the Demogorgon in exchange for sending Will right back to the Upside-Down. And she seemed so sweet...

So, will we see Barb — the real Barb — when Stranger Things returns for Season 2 (just confirmed by Netflix yesterday)? Matt Duffer wouldn't say concretely whether the character will make a comeback, but told IGN that — one way or another — she'll be avenged.

"Barb will not be forgotten," he said. "We'll make sure there's some justice for Barb. People get very frustrated, understandably, that the town doesn't seem to really be dealing with Barb. That stuff is all happening, we're just not spending any screen time on it. It's not like her parents are like 'Oh, Barb left.  She died!' Season 1 actually takes place over the course of six or seven days, it's a really short period of time."

Check out the clip and hang tight for more Stranger Things Season 2 details.

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