During Supergirl's freshman season, a number of episodes revolved around Kara's (Melissa Benoist) place as Cat Grant's (Calista Flockhart) assistant, but once Cat departed for places unknown and Kara was confident in her role as a heroine, the series smartly chose to focus on larger, more otherworldly issues, like Mon-El's (Chris Wood) secret identity as a prince and the drama that accompanied that particular revelation.

However, Kara's chosen profession and desperate desire for the truth returned in Monday's "Ace Reporter," just in time to make a pointed political statement about the necessary role journalists play in society. Now we could argue about how much Kara really cares about the truth given how little interest she's shown in journalism since losing her job at CatCo, but there's also no point.

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Of The CW's four superhero series, Supergirl is the most suited for social commentary because by nature it lends itself to discussions of particular relevance, including race relations, human rights and the fight for truth and justice. So once the series was finished laying the groundwork for the season's big conflict with Mon-El's mother Rhea (Teri Hatcher), it only made sense that Kara would once again pull out her paper and pen, push up her glasses and get to the bottom of Jack Spheer's (iZombie's Rahul Kohli) sketchy Biomax nanorobots.

That the hour also served as a way to add more depth to the character of Lena Luthor (Katie McGrath, who was recently promoted to a series regular for the show's third season) and maybe push her toward embracing the more traditional attitude of a Luthor meant "Ace Reporter" was not just a stand-alone episode featuring a standard villain-of-the-week but also an hour with the potential to push the show's season-long arcs forward.

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Melissa Benoist and Katie McGrath, <em>Supergirl</em>Melissa Benoist and Katie McGrath, Supergirl


As it stands, Lena doesn't regret her choice to move to National City and is proud of the work she has done at L-Corp since taking over from Lex, but the death of her former boyfriend of two years — with whom she'd just reconnected — also has her worried about the person she'll become as a result. And we should be worried, too. In addition to the threat still posed by Cadmus, Rhea's arrival at L-Corp with a proposition for Lena in the final moments of the episode can only mean one thing: big, bad things are coming.

Will Lena embrace the darkness that accompanies being a Luthor? Will she choose to ally herself with Rhea out of a desire to make people suffer the way she has suffered? Or will she remember what Kara said, when she promised to always be her friend and protect her? We'll find out soon enough; Supergirl's second season finale airs Monday, May 22. It's time to buckle up.

Supergirl airs Mondays at 8/7c on The CW.

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