At Comic-Con International in San Diego, news broke that Jane the Virgin standout Yael Grobglas is set to play the villainous Psi in the third season of Supergirl. The news likely led to more than one comic book fan asking, "Psi who?" The villain is certainly one of the more obscure Supergirl villains, but she is also one of the oldest Supergirl villains and for a show that is filled with mostly villains who are really Superman foes, it is good to see a traditional Supergirl antagonist appear on the series. We'll fill you in on everything you need to know about Psi ahead of Supergirl Season 3!

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After years of being one of DC's most popular features as both a backup in Action Comics and as a lead feature in Adventure Comics, Superigirl finally got her own series in 1972. That series ended up being short-lived, as in 1974, she was merged into the oversized Superman Family along with all of the other Superman supporting cast solo books (like Superman's Girl Friend, Lois Lane and Superman's Pal, Jimmy Olsen). That series lasted until 1982. When it ended, Supergirl was once again given her own solo series, titled The Daring New Adventures of Supergirl by writer Paul Kupperberg and artist Carmine Infantino (Kupperberg had taken over the Supergirl feature in Superman Family towards the end of that series' run). Kupperberg had lived in Chicago for a number of years, so Supergirl also moved to the Windy City to set up shop in this new series, where she enrolled in college in the city (one of her neighbors was a friend of Kupperberg's from Chicago named John Ostrander...yep, the same John Ostrander who later became a famous comic book writer himself!).

Comic books, as you all well know, are often used as allegories for things going on in the world and with Psi, Kupperberg was tackling the concept of "urban decay" through this new villain. Psi was a young mutant named Gayle Marsh who had telepathic abilities. She was taken in when she was just a teenager by a scientist, Daniel Penderghast, who trained her in the use of her powers to help him in eliminating the "decay" in the world.

He warned her of the people with powers who would be out to stop them in their mission and when Gayle bumped into Linda Danvers, she got a sense of Linda's immense powers as Supergirl and it disturbed Gayle greatly. She rushed to Penderghast to let him know that she had encountered one of the beings that he had warned her about. He told her that the time had come for them to put their plans into effect. Penderghast was super creepy.

It was not made explicit, but it certainly appeared that there was a sexual element to their relationship and considering that Penderghast was her legal guardian, it's all so very disturbing. Even more so when she attacks Supergirl at the end of the issue and reveals her new costume and codename as Psi. How unsettling is it that that skimpy thing is the outfit that Penderghast picked out for her to wear into battle!

The problem with Penderghast's plans was that Gayle was just too good of a person deep down to really embrace his methods. She believed him when he told her that there was a threat of "decay" in the world, but she was unwilling to believe that killing Supergirl would serve that goal.

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Despite kicking Supergirl's ass with her mental powers, Psi eventually dropped her attack and flew away in despair. She turned to her mentor, but her deranged teacher decided that this was proof that she was part of society's decay, so he tried to kill her. The resulting fight ended up with Psi somehow using her powers to transform Penderghast into a living symbol of Decay itself!

Supergirl battled Decay in the next issue, but ultimately, Psi realized that she had to fix what she had caused, so she decided to just kill Decay.

Psi then stumbled off in a state of despair and Supergirl just sort of let her go. That was it for Psi in that series, and Supergirl died a few years later and then found herself erased from DC's continuity. The next time Psi showed up, she could not reference her past with Supergirl, so instead, she had a total break with reality, losing her memory. In 1987, former Supergirl neighbor, John Ostrander, launched Suicide Squad, a series about comic book supervillains working their sentences off with the government. While members would occasionally die, the group as a whole tended to get out all right. However, in 1988, Ostrander and Kupperberg decided to do a different twist on that idea. They did a Doom Patrol (which Kupperberg wrote before Grant Morrison revamped the series) crossover with Suicide Squad and Psi was on a short-lived version of the Squad, with the government promising to help her find her memories (the issue was drawn by Erik Larsen and Bob Lewis, in one of Larsen's earliest mainstream works).

The Squad was in the Soviet Union to rescue a captured Hawk (of Hawk and Dove fame). The Rocket Red Brigade showed up and in the battle, Psi was tragically killed, as Negative Woman (who was Russian herself) was distraught over the senselessness of this young woman dying for a cause she had nothing to do with...

That was it for Psi for the rest of her Pre-New 52 career (outside of being resurrected as a Black Lantern along with other Suicide Squad victims during a Secret Six crossover with Blackest Night).

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In the New 52, she was introduced by another former Supergirl writer, Sterling Gates, in the A.R.G.U.S. miniseries during Forever Evil, as a being from another dimension who communicates only telepathically. She doesn't even have a mouth!

Psi is also currently being featured in the pages of Supergirl post DC Rebirth following an introduction in Batgirl Annual #1 (where they bust Gayle out of a prison she was being held in)...

Here she is in a recent Supergirl issue...

Pretty much either version of Psi's origin (manipulated college student or other-dimensional being) would work well for the Supergirl TV series. It is always good to see actual Supergirl foes on the series!