In search of a nemesis, Harley goes after Batman, but ends up with an adolescent Robin, making her the laughing stock of the criminal underworld.

When Harley suffers a paralyzing identity crisis, her crew must enter Harley’s mind to free her with the help of Dr. Psycho’s telepathic powers.

When Clayface loses his arm in a heist, it turns out to be not only evidence for Jim Gordon, but also a key witness against Harley and her crew.

Harley recruits her friend and mentor Queen of Fables to help her steal a force field from STAR Labs, to steal a weather-changing machine, so she can impress the Legion of Doom. Meanwhile, Poison Ivy dates Kite Man.

Harley gets an invite to the Legion of Doom’s prospective members party, but Ivy learns that she's the one they're really interested in.

Now a member of the Legion of Doom and The Joker’s equal, Harley finds herself spending time with him. Will she slip into her old ways?

Harley must rescue Ivy from the clutches of Scarecrow, who’s trying to harvest her pheromones to make a super toxin that turns plants into sentient monsters.

Harley thinks the Legion of Doom is behind Ivy's capture and the tree monsters currently ravaging Gotham. But it's a trap!

In the season finale, Harley has her final showdown with the Joker, when [spoilers] [spoil] [spoilers]. Will they [spoiler]? Maybe. But you can bet they [spoiler]!

Harley & Ivy team up with Catwoman to steal a museum artifact that’s been boobytrapped by Dr. Trap. Meanwhile, Dr. Psycho tries to prove himself as a leader.

When Harley and Ivy spot a seemingly sane Joker, they debate whether people can change at their core, revisiting a flashback about Harleen Quinzel's first day at Arkham Asylum.

While Harley & Ivy deal with their post-kiss awkwardness, the President tells Gordon that he must get rid of Harley to put Gotham back on the map.

Alone on Christmas Eve, Harley reconnects with a now-sane Joker and heads to Wayne Tower, where their dinner is interrupted by an escaped Riddler and ParaDemons.

In order to defeat Psycho's army, Harley & Joker need to track down Fables' storybook with the Justice League inside.

Psycho unleashes a mind-controlled Ivy, Clayface, and King Shark on the Justice League who are trying to free Gotham.

After Harley receives access to Bruce Wayne's mind, she gets stuck in an endless loop of his most formative memory.

When an inadvertent plant zombie apocalypse breaks out in Gotham, Harley fights to save the city, while Ivy embraces her inner supervillain.