Well, there is no denying it. Batman is a hot commodity right now. You can say that at nearly every point in time, because he's one of the most prolific superheroes ever, if not the most prolific. Also, thanks to "Suicide Squad," for better or for worse, Harley Quinn is now a hot commodity. DC Animation has made several Batman movies recently, so it would only make sense that they would make a movie where both Batman and Harley Quinn team up together.
I sure do wonder what The Joker will think of this one.
It looks like Poison Ivy along with some kind of green monster that I don't recognize, is trying to turn everyone on earth into green monsters. So Batman and Robin will team up with Harley Quinn to stop her. I wonder if since Harley Quinn and Poison Ivy know each other, Quinn can probably get to her better than Batman alone? That's my best guess as to why they would be teaming up. Even though it still doesn't make too much sense. Batman is the World's Greatest Detective, he can get to anyone he wants. Including Ivy.
No matter what though, I enjoy reviewing DC's animated movies on my site, so I look forward to seeing this one. By and large, the DC Animation does a good job with their movies. I am hoping for another fun one to enjoy!