This week's “Arrow” has not one, but three future super-villains — and a dozen or so super-soldiers — to contend with. And if you’re excited about that possible “Flash” spinoff, well, Grant Gustin doesn’t make an appearance... but hopefully, fellow cast members Danielle Panabaker (“Justified”) and Broadway actor Carlos Valdes will do.

Since Isabel seized control of Queen Industries last week, the episode opens with Oliver, Felicity, and Sara blowing up their own Applied Science Center to keep Deathstroke away from the centrifuge he needs.

So Deathstroke shows up to the Arrowcave and swipes the skeleton key (from the Clock King episode a couple months back), which he uses to break into a S.T.A.R. Labs warehouse where he confronts Caitlin Snow (Panabaker) and Cisco Ramon (Valdes).

Those two will be part of the new “Flash” series, slated to debut this fall if The CW picks it up. Snow and Ramon are engineers employed by the company responsible for the particle-accelerator explosion that gives the Flash his powers. When we meet them, though, they’re just doing inventory on a bunch of science experiments.

Originally, Grant Gustin was to appear in the episode as Barry Allen, but for the sake of continuity, producers decided that he’s still in the coma he was put in back in “Three Ghosts.” By bringing in Panabaker and Valdes, they honored the intent of doing a “Flash”-related episode without, in the words of “Arrow” executive producer Marc Guggenheim, “paying Grant Gustin a lot of money to sit around with his eyes closed just unconscious the whole episode.”

[Related: Get a First Look at the New 'Flash' Costume]

Ramon and Snow seem friendly enough now, but their characters are based on the sometime super-villain Vibe and the always super-villain Killer Frost, so it remains to be seen what direction “Flash” takes them.

#arrow is making me wanting #flash tv series to start already! Stop teasing me with Vibe and Killer Frost! — Michael John (@MJMTIII) April 17, 2014

"You feeling a bad VIBE of this guy?" #ISeeWhatYouDidThere #Arrow — DCU Movie Page (@dcumoviepage) April 17, 2014

Deathstroke steals what he needs, and when Oliver tracks him down, he’s already used the device, which transfuses one person’s blood into multiple people. Only instead of using his own blood, Slade drains Roy (Colton Haynes) instead. In the ensuing melee, Diggle kills Isabel.

Well, Diggle shoots Isabel. In the last scene, we see her eyes, with blood streaming from them like we’ve seen with Mirakuru recipients in the past. Executive producer Andrew Kreisberg admitted to the Hollywood Reporter that this paves the way for Isabel to become Ravager, a super-villain that has appeared in five separate incarnations in the comics. "Now that she's got the evil juice, as I call it, she's going to be Ravager. It's amazing."

[Related: 'Arrow' Postmortem: EP Andrew Kreisberg on the Cure, Isabel 2.0, and Laurel's Secret]

This was a little unexpected, especially since the name Isabel Rochev is already the name of a DC super-villain, The Queen. Like her “Arrow” counterpart, The Queen was born in Russia, fell in love with Robert Queen, took over Queen Industries, and generally makes life for Oliver miserable.

The Ravager is comic-book Deathstroke’s apprentice and daughter. Does that mean that Isabel is also Slade’s daughter?