Warning: Full spoilers for the episode below.
A lot has changed with Supergirl this season, not least of which being the transition to Sunday nights. Several series regulars have taken on drastically reduced roles, while new players are rising up to fill the void. It all feels like a significant and very intentional shift in direction from Season 3. And given how underwhelming that season was in some respects, that’s not a bad strategy. In fact, it’s one that pays off pretty handsomely this week. After one episode, there’s already reason to feel enthusiastic about the show’s future.
Judging from “American Alien,” the focus this year seems to be as much about bringing the series back to the tone and approach of Season 2 as it is blazing new ground. Individual character arcs from Season 3 are clearly influencing the direction of the show (J’onn and Winn’s retirement, Lena and Supergirl’s estrangement, etc.), but the Reign storyline in general barely seems to matter at this point. Instead, the focus has shifted back to National City’s growing anti-alien hysteria and drama within the Luthor family.
Source: IGN.com Supergirl Season 4 Premiere: "American Alien" Review