As soon as the news hit that Margot Robbie's Harley Quinn will star in her own film, titled "Gotham City Sirens," the comic book world has been abuzz about what other DC Comics characters might also appear. The most likely candidate is Poison Ivy, as she actually was a part of the comic series of the same name. However, Harley and Ivy's relationship was established well before that title debuted in 2009, and has continued beyond it.
While we wait for the official announcement of Poison Ivy's involvement and casting, we thought it would be interesting to look back at the history of Harley and Ivy's relationship on television and in comics.
Harley Quinn and Poison Ivy first met on the "Batman: The Animated Series" episode "Harley and Ivy," which premiered Jan. 18, 1993.
In it, Harley Quinn and Joker break up after he insulted her one time too many (and, you know, threw her out of their hideout). She intended to show the Joker she was just as good of a criminal as him. While robbing a museum of a valuable gem, she runs into Poison Ivy, who was stealing plants. They helped each other escape, and as they drove off, Ivy remarked, "This could be the beginning of a beautiful friendship."
The two became a very successful criminal duo, but all the while, Harley couldn't forget "Mr. J," which enraged Ivy, as she felt the Joker treated Harley horribly. During their time together, Ivy injected Harley with a chemical that gave her the same resistance to toxins that Ivy had. Later, Harley would discover this chemical also helped her strength and agility (it is debatable whether that was ever made explicit in the actual cartoons, or if it was just something that was confirmed in a DVD commentary). In the end, Harley betrayed Ivy by contacting the Joker, but when he showed up to make off with all of their stolen loot (as he was dismayed that not only did Harley survive being kicked out his gang, but that she now rivaled him as the top crook in Gotham City), he also tried to blast Harley with his poisonous flower on his boutonniere. Only Ivy's chemical saved Harley. Ivy and Harley escaped, exclaiming that "No man can take us prisoner!" -- and sure enough, it was Renee Montoya who took them down, with a perfectly aimed gunshot of a tire in their getaway car. They went to prison still as friends.
The Harley/Ivy duo made their comic book debut a few months later in "Batman Adventures" #12 (by Kelley Puckett, Mike Parobeck and Rick Burchett), in a story that also served as Harley Quinn's comic introduction. She and Ivy ran afoul of Barbara Gordon, who dresses as Batgirl for the first time in that story.
Harley and Ivy do not team up again during the initial two-season run of "Batman: The Animated Series," but they reunited when the show returned in 1997 in the premiere episode of "Batman: The New Adventures." In "Holiday Knights," they use Ivy's chemicals to brainwash Bruce Wayne into becoming their slave.
Harley and Ivy teamed up a few more times in this iteration of the Batman cartoon.
Meanwhile, Harley Quinn made her official entrance into the DC Universe in 1999's "Batman: Harley Quinn," by Paul Dini, Yvel Guichet and Aaron Sowd. It was released during Batman's "No Man's Land" crossover event, in which Gotham City had been cut off from the rest of the United States following a devastating earthquake. The disaster was what first led Dr. Harleen Quinzel to the Joker as Harley Quinn, as her origin was basically the same as the cartoon, only she was put into an asylum when she let the Joker go. However, the earthquake caused everyone to abandon the asylum, allowing Quinzel to escape and join up with the Joker (in the process adopting a costume and the name Harley Quinn). The Joker grew sick of her and tried to have her killed. Poison Ivy, who spent No Man's Land cut off from the rest of the city, as she protected the plants of Gotham, ended up saving her and giving her the same chemicals from the animated series, resulting in Harley becoming stronger and more agile.
Despite all of that, Harley still ended up going back to the Joker.
By that point, however, Harley and Ivy had become a standard accepted team-up. Paul Dini and Bruce Timm even created a miniseries, "Batman: Harley and Ivy." that spotlighted the pair's adventures together in the "Batman: The Animated Series" continuity.
A few years later, in 2009, Dini and Guillem March launched "Gotham City Sirens," an ongoing series about the team of Harley Quinn, Poison Ivy and Catwoman.
The Sirens were an interesting group, in that they weren't exactly heroes, but neither were they criminals. They had a number of adventures in which they were mostly on the side of good. As it turned out, in the end, Catwoman saw something good in both Harley and Ivy, and tried to reform them, even working out a deal with Batman in which he would leave the pair alone while she worked with them. However, when all was said and done, it was not to be, as Harley betrayed the group by breaking into Arkham Asylum to kill the Joker (but instead, decided to free him). When Poison Ivy confronted her, Harley cut Ivy to the bone by revealing tshe knew the truth: that Ivy was in love with her.
She then used Ivy's stunned silence to attack her, allowing her to escape with the Joker.
Angered by Harley's actions, Catwoman arranged for Harley and Ivy to be captured. They naturally escaped, and the three had a big battle, after which they all went their separate ways (Ivy had seemed to come to terms with the fact that she did love Harley, but it was unclear if it was romantic love or platonic love).
The true nature of Harley and Ivy's relationship had always been a subject of fan speculation. Dini even teased about the situation, as in 1998's one-shot "Batgirl Adventures," illustrated by Rick Burchett, where Batgirl is even curious about Harley and Ivy's deal.
Ultimately, in 2015, the writers of Harley Quinn's ongoing series, Jimmy Palmiotti and Amanda Conner, confirmed that "Yes, they are Girlfriends without the jealousy of monogamy."
It was really in Harley Quinn's current series, though, that their relationship developed even further, as they were being a lot more intimate, like this shower scene from "Harley Quinn" #3:
Recently, however, in "Harley Quinn" #8, Ivy has temporarily ended their relationship when Harley wanted them to move in together, as Ivy needed more time to herself than she thought that Harley was prepared to give her:
That's where their relationship now stands.
As you can see, there is plenty there for filmmakers to work with in a possible "Gotham City Sirens" film. It will be interesting to see what they do with the Harley/Ivy relationship in the film. Will they be girlfriends in the movie? Time will tell!