The Joker faces off with Catwoman in issue 9 (Sept/Oct 76), the final issue of his book, in a story by Maggin, Novick and Blaisdell. Catwoman had last appeared in Batman the previous year.
The story centres on an actor, Benny Springer, famous for the comedic movies that he makes alongside his trained cat. Catwoman kidnaps both Springer and the cat, although this gets complicated by the Joker, who had been planning to kidnap Springer himself, and impersonate him.
Catwoman plans to ransom Springer and his cat back to the film studio, though it is interesting to note that she also hopes her caper will draw Batman's attention. As is often the case in the Joker's stories, the guest star gets more of the focus than the Joker does.
At one point it appears that Batman has shown up, and Catwoman is quick to plant a kiss on him. Too quick. This is actually the Joker in disguise. He actually adopts quite a few disguises in the course of the story, and he is not the only one.
Benny Springer takes advantage of the fight between Catwoman and the Joker to get away, but then disguises himself as the villain and returns, claiming the real Joker is actually Springer. He takes this huge risk in order to retrieve his pet cat. The two Joker wind up fighting, to Catwoman's amusement. Catwoman decides to let the cat show her which one is his master, but Springer is able to signal the highly trained cat to go to the real Joker. Catwoman shoots the Joker with a tranq dart, but Springer traps Catwoman in her own cage.
Two-Face cameos as the story concludes. The Joker had maanged to splice a frame of himself into the master cut of Springer's newest film. It does make a nice note for the series to go out on. Still, I wish the series had lasted longer. The next issue was billed to pit the Joker against the entire Justice League.
Of the three villains in the issue, the first to return is Catwoman, who shows up the following month in Batman Family. The Joker is back a couple of months after that, in the Strange Sports Stories issue of DC Super Stars. Two-Face has to wait till the following year for his return, in Teen Titans.