Every Arrowverse Crossover Ranked From Worst To Best
4. World's Finest
When Supergirl made its debut on CBS, it wasn't long before fans started calling for a crossover between it and The Flash. They did so for a number of reasons - yes, Melissa Benoist and Grant Gustin's shared Glee history obviously played a large part in that, but it was also down to the fact that they were convinced the light-hearted tones of both shows would blend together really well. They were right.
Worlds Finest arrived just before the conclusion of Supergirl's debut season and it was huge deal given that it was on CBS at the time and The Flash was on The CW, but the cross-network crossover was nothing short of super.
Utilising the concept of the multiverse that had been introduced in The Flash's second season, the episode saw Barry accidentally travel to Earth-38 and get stranded there in the process. And when he crossed paths with the Girl of Steel, it wasn't long until a super adventure kicked off - as the pair ended up facing off against the villainous duo of LiveWire and Silver Banshee.
A light-hearted, joyous and utterly refreshing superhero smackdown, Worlds Finest was corny in all the right ways, as it highlighted the best of both shows while also using it to further Supergirl's ongoing narrative. It never took itself too seriously and yet still inspired a hopeful message - all while kicking off one of the most important relationships in the Arrowverse.
You really couldn't want any more from superheroes. This was glorious.