Harley Quinn exclaims that she and Lady Shiva are partners in an Advance Stake-out Class project, surprised at the thought, playing with her giant mallet, while Lady Shiva looks out for their target, via some binoculars. Annoyed, Lady Shiva says that Principal Waller clearly came up with the idea of pairing the two together, before going back to her binoculars.
Shiva asks Harley, whether she's seen any sign of Cheshire yet, but Harley says she hasn't, saying that Cheshire's a deadly assassin and that she's probably out deadly assassinating. Shiva tries to get Harley to stop joking around, in fear she'll give away their location, just Harley hooks her mallet underneath Shiva's binoculars, taking them from her. Harley asks why Shiva is taking it so seriously, with Shiva replying, saying it's a serious assignment.
Harley then looks through their binoculars at Shiva, saying she's so serious, that she bet's she doesn't even know a single joke, with Shiva turning around and angrily looking up the binoculars at Harley. Harley then takes her binoculars away from Shiva's eye-line and says, eye spy with my little eye, before seeing Cheshire jump down in front of her. Shiva then turns around, saying that what Harley's saying is not funny, but realizes Cheshire really is there. Both Shiva and Harley jump back onto the roof edge, as Cheshire extends her sharp fingernails, believing it to be hilarious.
Cheshire tries to take a swipe at the two, as they immediately jump out of the way, jumping off the roof, with Shiva managing to grab hold of a pole and swinging off of it, as Harley falls right through the roof of a fruit stand, falling and smashing a crate of oranges. The girls then head off after Cheshire, climbing up the stairs. However when they arrive on top of the roof, they find no-on there. While creeping across the roof, Harley jokes that she and Cheshire should join up for a variety show, complimenting Cheshire on her disappearing act. Shiva then hushes, angry that Harley can't keep quiet and that she doesn't want to fail as an effect of it.
Harley then says, she wouldn't have to entertain herself, had Shiva just told a joke. Angry, Shiva gives in and gives Harley a joke, being a Knock knock joke, with Harley saying who's there. Just then Cheshire appears behind Harley, causing Shiva to say duck, as she delivers a powerful blow to Cheshire. Harley laughs at the sight of Cheshire's knockout, saying she thinks Cheshire got the joke. Cheshire is then arrested, as Harley compliments Shiva's comedic ability, saying that she's great with a punchline, causing Shiva to giggle, and then ask Harley to not tell anyone.
- The title references the 1970s TV series of the same name.
- Harley Quinn makes a reference to the Joker's "Why So Serious?" line from The Dark Knight.
- This webisode was titled "Odd Couple" on YouTube.
- This episode was listed as the twenty-fifth webisode of season 2 on YouTube.