SPOILER WARNING: This article contains spoilers for the latest episode of "Supergirl," "Medusa."

Tonight's "Supergirl" episode doesn't lack for action -- it's got a weaponized virus, a Luthor showdown, a breach from Earth 1, and Kara cooking a turkey with her heat-vision, to name a few -- but there's action, and then there's action. Surprisingly, the most unexpected developments in "Medusa" are of the romantic variety.

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First up on the love train, Kara. A mere one episode after the revelation that a certain Daxamite has a little thing for the daughter of the House of El, an ailing Mon-El lays a kiss on Kara. Believing himself to be on his deathbed, he first tells her that he's ready to die, then says she looks beautiful "with the weight of so many worlds on [her] shoulders." It's a sad and sweetly romantic scene, which leads to the aforementioned unexpected smooch.

Supergirl-Mon-El

By episode's end, Mon-El seems to have forgotten the moment, and Kara follows his lead in pretending it never happened. Luckily for those who like happy things, it's not the only romantic interlude of "Medusa." Kara's not the only Danvers sister to get a love scene in the episode, and Alex's smooch will likely leave viewers in a much better mood.

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Weeks after telling the newly-out Alex that she wants to be friends, a brush with death pushes Maggie, as it does Mon-El, to go after the object of her affections. Showing up at Alex's doorstep with a pizza and a six-pack and telling Alex that life's too short to not "kiss the girls you want to kiss," Maggie plants one on the D.E.O.'s finest doctor-scientist-special agent.

Supergirl-Maggie-Alex

Surprising? Perhaps not. Still, two relationship-changing moments in one hour isn't an everyday occurrence, even in National City.

Check back later for CBR’s full recap.

Starring Melissa Benoist as the title character, “Supergirl” airs Mondays at 8 pm ET/PT on The CW. The series also stars David Harewood as Martian Manhunter, Mehcad Brooks as Jimmy Olsen, Chyler Leigh as Alex Danvers and Jeremy Jordan as Winn Schott and features appearances by Calista Flockhart’s Cat Grant as well as Tyler Hoechlin’s Superman.