The Big Bang Theory star Kaley Cuoco's Harley Quinn TV series has unveiled a first-look trailer for its Valentine's Day special.

The DC Universe show will return for a one-off holiday episode on HBO Max on Thursday, February 9 as Harley and Poison Ivy take a huge step in their relationship.

While Harley promises Ivy she is planning a "low-key" celebration of their love, their most intimate moment has some unexpected consequences by accidentally increasing the sex drives of all of Gotham City.

preview for Harley Quinn: A Very Problematic Valentine's Day Special trailer (HBO Max)

Related: Big Bang Theory's Kaley Cuoco marks pregnancy milestone with cute picture

Before long, The Riddler is proposing marriage to the Clock King and even Darkseid finds it in his cruel heart to fall head over heels in love.

"Ah man, you can't be mad at me for getting you off too good. That is not a thing," Harley insists when Ivy points out the state of Gotham City.

It's no surprise that Harley Quinn's one-off special is entitled A Very Problematic Valentine's Day Special — and if you still consider the plot tame, you'll also get to see Bane debating the male anatomy with Etrigan the Demon!

Even better news for fans is that the Critics' Choice Television Award-nominated animated series will be back for even more new episodes, as it was renewed for a fourth season last summer.

harley quinn and poison ivy in the harley quinn season 2 trailer
DC Universe

Series co-creators Justin Halpern and Patrick Schumacker are stepping back for season 4, having turned over the creative reins of the show to Master of None and Awkwafina Is Nora from Queens's Sarah Peters.

"We are ecstatic that HBO Max wants the story of Harley and Ivy to continue," Schumacker and Halpern said in a statement over the summer. "And we are equally thrilled that this next season will be in great hands with Sarah Peters as our showrunner and Ceci Aranovich overseeing animation production, as they have both greatly influenced the show with their brilliance since the beginning."

Harley Quinn: A Very Problematic Valentine's Day Special premieres on HBO Max on February 9 in the US. The series streams on All4 in the UK.

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Justin Harp

Night News Editor

Justin has been with Digital Spy since 2010, and in that time, has covered countless major news events for DS from the US. 

He has worked previously as both a reporter and sub editor for the brand, prior to taking on the position of Night News Editor in 2016. 

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