Oh, that sneaky Stephen Amell. When the Arrow star isn’t dropping return announcements for the DC drama’s 100th episode, he’s busy hanging with Supergirl. See for yourself, as Arrow and the Girl of Steel strike a pose in the latest crossover tease.

Amell shared a quick snap from continued production on the epic four-way crossover headed to screens this fall, as the Green Arrow meets Supergirl atop a roof in … maybe Central City? So many roofs, and non-descript cityscapes permeating these series and their Vancouver production.

Sadly offscreen is David Ramsay’s John Diggle, who promises a fairly fluid reaction to first seeing Supergirl streak across the sky.

Thus far, details of the actual crossover have been kept relatively under wraps, though we at least know the Supergirl series itself won’t factor in so much as the others. It also remains to be seen what brings Supergirl and Arrow to share any Earth, given that only Flash managed to visit Kara’s Earth previously.

We’ll see a longer look at all the CW DC heroes teaming up tomorrow, but admire the view with Arrow and Supergirl above, and stay tuned for the latest from next week’s premieres.

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