7) Worlds Finest – Supergirl
It was a strange stroke of fate that, in the same week that Batman V Superman: Dawn of Justice was rearing its grey, gloomy head in cinemas, DC’s TV division offered up a much brighter take on the superhero crossover. BvS will have a longer shelf-life, but Supergirl‘s “Worlds Finest” was undoubtedly the more immediately lovable of the two.
Barry Allen aka the Flash accidentally crash-lands on Earth-Supergirl (later called Earth-38, as a reference to Superman’s birth year) – just in time to help Kara Danvers save National City from two crazed supervillains; Livewire and Silver Banshee. The episode was full of endearing moments – such as Barry proving his powers by getting everyone an ice cream – and it nicely set the table for more connections between Supergirl and the rest of the Arrowverse shows later down the line.