Warning: This article contains spoilers from episode 10 of the Flash. If you have not yet seen "Revenge of the Rogues", you may want to turn back now!
Now that the obligatory spoiler-warning is out of the way, lets talk Flash! More specifically, lets talk about that final scene.
By the end of the episode, Captain Cold and Heatwave have been defeated by The Flash, courtesy of some Ghostbusters-esque stream-crossing. Barry, being the upstanding citizen that he is, sends the two of them away to prison, but unsurprisingly, they don't quite make it there. In the final scene, Snart and Rory are having words in the back of the prison van when it is stopped and broken into, and Snart reveals that this was the plan all along. Most importantly, he greets their rescuer with the words "Hey, sis.".
First of all, I think it was very cool to see this new Rogue introduced in the same way as Heatwave. End of an episode, Captain Cold doing the talking, and a disembodied voice off camera. It keeps new fans guessing, while fans of the comic books are jumping up and down wondering what the character that they know is going to look like in this series. It also keeps the focus on Leonard - he is the number one Rogue, and by introducing people this way, it is made very clear that he is still very much in charge. Perfect.
Second, let's talk about who "sis" actually is. Leonard Snart's sister's real name is Lisa Snart, occasionally Lisa Star (because, let's face it, Snart really isn't the most appealing last name in the world). However, she is better known by her villainous alias - Golden Glider!
Like Captain Cold and Heatwave, Golden Glider doesn't usually have any real "superpowers," but instead uses technology for her life of crime. (Admittedly, in the new 52 she has some astral-projection-style abilities, but I don't think we'll see those in the series, given that her brother and Mick Rory are using technology.) As an ex-figure skater, her primary piece of tech is a pair of modified skates that give her the ability to skate on any surface, including air! It's going to make a pretty impressive display, and I can't wait to see what the show does with FX for her.
She also has a collection of jewel-weapons that allow her to hypnotize people, teleport, and use force fields and illusions. As an athlete, she's got speed, strength and agility on her side as well.
In the comics, she has blonde hair and sports a natty figure-skater style outfit and mask...which I'm pretty sure we won't be seeing in the show! Like Captain Cold and Heatwave, we'll probably be seeing a more "normal" choice of clothes, with some nods to the original costuming; maybe the "V" down the front, or the white and yellow/gold colors. Interestingly, Peyton List, who is playing Lisa Snart, is a brunette. I hope that she'll be changing that for the show though - just to keep continuity with the original character.
The introduction of Golden Glider could mean a few different things in terms of storyline for the show.
It's possible that she is simply brought in as another Rogue, and her character provides background and development for Leonard. However, I would like to see some of the elements from the comics appearing. We may well see her hypnotizing and trying to murder Iris West, which could be interesting. However, in the comics this is something she does once Iris is already with Barry; it may be a little random for Iris to be attacked in the show right now seeing as she has just moved in with her boyfriend. It may be obvious to viewers that Barry is in love with her, but as we saw in the last episode, the villains see Caitlin as a more appropriate hostage right now.
We could also see a couple of new Rogues being brought into play alongside her. Lisa's original Flash-hatred springs from the death of her lover, Top, at his hands. Top, a.k.a. Roscoe Dillon, is a villain who can spin incredibly quickly (which I promise, is more useful for crime than it sounds) and has a range of top-shaped weapons. It's possible that we could see Top appear, but I feel like it is somewhat unnecessary - it's more likely that the Golden Glider is anti-Flash simply because she is pro-Captain Cold.
The other (and more likely) possibility is that we see her creating Chillblaine. This, or more accurately, these are fighters created by the Snarts using some of his cold technology to fight for the Rogues. There have been several, and are most important because one of them eventually kills Lisa when he realizes that she is manipulating him. Now that is a story that I would love to see - as much as I love the idea of keeping Captain Cold around as a recurring nemesis for Barry in the great comic book tradition, I would also like to see some villains being thoroughly vanquished.
Wherever they decide to go with Snart, I'm thrilled to see a female villain join the boys. I really appreciate that both Arrow and The Flash seem to be keeping a good balance of male and female characters, and the time is right to include a female bad guy (bad girl?) for Barry. Like Heatwave, it may be another few episodes before we see her in the flesh (episode 16, according to IMDB), but I think it will be worth the wait!