Supergirl, “Nevertheless, She Persisted:” Through alien invasion, a temporarily mind-controlled super-cousin, an anti-alien weapons, the departure of her gratuitous super-boyfriend, and a teaser for next year’s big bad.

The Flash, “Finish Line:” Much drama ensues, Iris steps up, and Barry uses a technique against Savitar that he literally could have tried several episodes ago. Then we get a depressing teaser for next season, because CW still thinks we want a dark, mopey Flash.

Arrow, “Lian Yu:” Barry comes full circle, and past characters return.

Discussion below.