WARNING: The following article contains major spoilers for Heroes in Crisis #6 by Tom King, Mitch Gerads, Clay Mann, Tomeu Morey and Clayton Cowles, in stores now.

Right from its very first page, Heroes in Crisis has been rife with questions. Who killed the heroes at Sanctuary? What, exactly, is going on? Is Wally West really dead?

Five issues in, and Tom King and Clay Mann's murder mystery has only brought more questions. But with the arrival of Issue #6, illustrated by guest artist Mitch Gerads, one of the main questions fans had about the series is finally answered.

Ever since the release of Heroes in Crisis #1, fans have wondered why both Harley Quinn and Poison Ivy were at Sanctuary. Ivy, unfortunately, was one of the victims of the massacre, while Harley is still one of the main suspects. But both of them are technically villains -- so what were they doing seeking treatment at a recovery center for superheroes?

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Was Harley working there as a counselor? Were they both seeking treatment because the two of them have been painted as antiheroes more than villains in recent years? Turns out the answer is neither.

In Heroes in Crisis #6, we finally learn the truth about why both characters were in Sanctuary at the time of these grizzly murders, and it turns out it was more a terrible case of being at the wrong place at the wrong time. Somehow, Harley Quinn learned about Sanctuary and its purpose, and she broke in to seek treatment for all the years of abuse she suffered at the hands of the Joker.

As for Poison Ivy, her only crime was being a good friend. While she was a legitimate, "on the books" patient (she was admitted following her Batman storyline where she took over the world), she snuck herself and Harley into Sanctuary's virtual reality room in order to help her friend in her sessions. When the two talk, Ivy tells Harley that as soon as Batman, Wonder Woman and Superman find out that she's in there with Harley, they will promptly kick her out. This confirms that Harley is definitely not there by invitation, making their involvement in the imminent massacre all the more tragic.

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Now we know the truth. Harley was never supposed to be there, and it only adds more weight to Ivy's death. She was trying to lend support to her friend, and she's the one who ended up dying. This might explain why Harley's been acting irrationally (well, more irrational than usual) in Heroes in Crisis. She knows that Ivy's dead because of her, and she's reeling from that loss.