Fans of either Supergirl or The Flash have been racing for details since CBS first announced their March crossover, and the super-details have finally arrived! Not only do we have our first poster of the “Worlds Finest” race, but also official story details on the big universe-hopping teamup.

In addition to a cheeky new poster advertising a race between Barry and Kara (come on, you knew it had to happen), the first March 28 plot details confirm a villainous teamup we glimpsed on set earlier:

Kara gains a new ally when the lightning-fast superhero The Flash suddenly appears from an alternate universe and helps Kara battle Siobhan, aka Silver Banshee, and Livewire in exchange for her help in finding a way to return him home.

 

 

The poster itself is an homage to a classic Superman #199 comic, in which the Man of Steel ran alongside the Scarlet Speedster. Other than some background easter eggs, expect Kara to fill that role.

At the very least, we also know that while “Worlds Finest” airs on March 28, the prior week’s Flash outing “Flash Back” episode will see Barry again traveling through time, which could well end with him somehow breaching dimensions to Kara’s National City.

We’ll find out more on the road to March 28, but enjoy the poster above, and stay tuned for more “Worlds Finest” details of the big Supergirl-Flash crossover!

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