Saving the world takes a lot of time out of one's day, and presumably that's why none of these people have ever watched a television show or movie before. That's the only possible excuse for the actions of some of the characters in "Homecoming," the contrived and somewhat ludicrous "Supergirl" episode which brings Jeremiah Danvers back into the fold. Their schedules are so full, no one besides former slacker Mon-El recognizes the cliché of the mysteriously returned hero who is secretly a bad guy when it strolls into the DEO. Get these people a Netflix account ASAP. Perhaps Winn could share his password with a few others.

It's one of the great contradictions of "Supergirl" that even if there's a dearth of logical behavior and original storytelling, this is a series that hits even when it misses. No episode is ever all bad (and a few have been all good), and this undeniably silly set-up still packs a hell of an emotional punch. That's thanks largely to unsurprisingly terrific performances from Melissa Benoist, Chris Wood, Jeremy Jordan and particularly Chyler Leigh, who pounces on every opportunity to dig into Alex's hurts and sorrows. It's a turn so strong that even as Alex does some truly stupid things, you understand why. Leigh commits fully to Alex's blind loyalty, and so instead of a story where a bunch of very smart people ignore a bunch of red flags and reject common sense, we get a story of two young women who lost their father and how their joy blinds them to the obvious.

So here's how that story begins: after a cute morning-after scene with Kara and Mon-El (she's stopped several robberies, helped a tugboat and delivered a littler of puppies before he's even found his boxers), the new lovebirds get called to the DEO. Cadmus is transporting some very powerful weapon, and because they got a very convenient and handy alert, Kara and J'onn are in a position to intercept this prize. It's more surprise than prize, however: the super special secret weapon Cadmus conveniently let the DEO capture is Jeremiah Danvers.

This is great news... or is it? Of all the people who take basically no precautions after the miraculous Danvers reemergence, J'onn's the one who comes out of it looking the worst. How did he not notice that he couldn't read Jeremiah's mind before? How is it that no one on his staff noticed that his "damaged arm" was actually a weapon? How is there no protocol for making sure agents captured by an enemy organization aren't coming back brainwashed? In short, what the hell is going on at the DEO? If they missed this, how on earth can they be trusted to protect Supergirl's identity? She started showing up in full reporter drag a few weeks back.

Still, the DEO, his daughters, and even his wife embrace him with open arms. The only one to wonder at the convenience of all this is Mon-El, who has not necessarily come across as the most observant person prior to this point. Wood does a great job tracing Mon-El's slowly mounting suspicion and his completely understandable frustration with the inexplicable foolishness of his normally sharp peers.

After that frustration gets him bounced from the Danvers Family Reunion Margarita Bash (which features a terrific scene between Helen Slater and Dean Cain), Mon-El breaks new ground in this episode: he does something sensible and calls Winn. While Jeremy Jordan hasn't gotten many of his own storylines this season, he's cemented the Supergirl Cisco as a smart guy who recognizes trouble when he sees it, and Winn sees the trouble nearly the moment Mon-El points it out. Mon-El and Winn set about keeping an eye on Jeremiah, and because "Supergirl" rarely lets a good plot build over time, they're rewarded for their efforts right away.

After a tour of the DEO with J'onn, Jeremiah sneaks into a super special DEO computer room and breaks into some highly classified files and a watching Winn soon repeats this to Mon-El. Together they tell Kara, and these two guys together are able to do what the somewhat socially inept Mon-El couldn't do solo. The rational part of Kara's brain kicks back into action, and together the three of them confront Jeremiah. He denies it of course, busting out an excuse so flimsy that it barely makes sense, let alone seems plausible. For Alex, however, it's more than enough, and Kara's willingness to question the family patriarch leads to an ugly confrontation between the sisters.

Related: Supergirl: ‘There’s a Plan’ for Dean Cain and Teri Hatcher to Share a Scene

Once the weapon (powered by Supergirl's heat vision, supposedly stolen from her when she and Mon-El were captured -- a story that, once again, only Mon-El thinks to question) is on the move, the sisters Danvers have to put aside their differences, round up some minions, and bust into an empty warehouse. Whoops, they've been CADMUSed, something J'onn realizes when Jeremiah hightails it out of the command center and into an elevator. Their ensuing fight scene shows off Jeremiah's enhanced arm (somehow overlooked in the X-ray or something?), an advantage that helps him kick the holy crap out of The Artist Formerly Known as H'annk Henshaww. By the time both Winn and J'onn come to, Jeremiah's gone, and so are whatever files he stole.

But wait! In the second sensible action of the episode, Winn reveals he planted a tracker on Jeremiah. Alex and Kara take off to confront their traitorous dad, though they have to split up when Kara needs to stop a train from tumbling through a bombed-out bridge. Once alone, Alex attempts to force Jeremiah to stop and come back in with her, but her father refuses to come back, telling her he'd willingly die first. Alex needs some answers, but Jeremiah only says he did it all for her. "Family is complicated," he says, taking time out from being a terribly unconvincing double agent to dispense some fatherly wisdom. She doesn't shoot him -- not even in the leg or something like that! -- and he leaves.

After that, the sisters Danvers retreat to their corners to lick their wounds and be comforted by their incredibly attractive significant others. Following some good advice from Winn, Mon-El actually listens to what Kara needs, and they seem set for a cozy sad night of sitting on the couch with a blanket when Kara's phone rings. The files Jeremiah stole were those for the National Alien Registry, and suddenly there's no more time to be sad.

"What do we do now?" asks Mon-El. Kara then gets what's perhaps the most "Supergirl" line of the episode: “We get up.” “Yeah we do,” he replies, and they're off.

"Homecoming" isn't the strongest of "Supergirl" outings, but it's solid, anchored by great performances (and an acceptable performance from Dean Cain who, let's face it, probably did the best he could with what he got). Would it have been more interesting to watch Kara struggle with her suspicions, rather than Mon-El? Sure, but it's entertaining all the same. Add in some intrigue -- what is Cadmus building? Who is Mon-El really, and how does Jeremiah know? What kind of bourbon has Alex been slamming? -- and you've got one of the stronger entries of the season. Quite something for an hour that, were it not for a stellar and smart cast, could have been nothing but silly.

Yes, it's still silly, but it also stings, and that's a much more important task.

Airing Mondays at 8 p.m. ET/PT on The CW, “Supergirl” stars Melissa Benoist, Mehcad Brooks, Chyler Leigh, Jeremy Jordan, David Harewood and Chris Wood.