Like so many of the great screen romances, April (Hannah Marks) and Clara (Liana Liberato) fall in love on the dance floor in “Banana Split,” intoxicated perhaps by the free-flowing tequila at the house party they first meet each other at, but just as likely the comfort they have in each other’s company. Though they’ve only known each other mere hours, with Clara having just moved to town from Fresno, she’s holding April’s hair by the end of the night as she throws up, gently stroking it to make her feel better, though what would really make April feel better is the one thing she couldn’t possibly give.

“I really wanted a reason to give you a black eye,” says April, who only meets Clara after learning that she’s dating her ex-boyfriend Nick (Dylan Sprouse) after a two-year relationship, though the feelings that develop so rapidly between the pair they aren’t about to let that small detail get in the way of a clearly more meaningful coupling. It is a fiendishly clever premise that Marks and co-writer Joey Power have concocted and it’s no surprise that they chose a master of light both in a literal and figurative sense in Benjamin Kasulke, the long-cherished cinematographer amongst Seattle filmmakers, to make his directorial debut on.

Not only is there a great casual beauty in how “Banana Split” looks, with cinematographer Darin Moran envisioning a sun-dappled summer in SoCal where Willy Wonka might feel at home, but in the sheer goodness to be found in April and Clara’s friendship, soon going bowling and shopping at thrift stores together. After setting ground rules that involve not mentioning Nick, the two seem to spend more time with each other than they ever did with him, but with just three months until April enrolls in Boston University, ready to kiss SoCal and her memories of high school goodbye, it becomes apparent that Clara could just be a summer fling, particularly if Nick were ever to find out they even know each other. (It’s through Instagram that April learns who’s hooking up with her ex.)

Marks and Power, who so savvily tackled the perils of committing to someone too soon in the recent SXSW hit “After Everything” (previously titled “Shotgun”), once again find a shrewd way to rework tropes of the romcom into something entirely new, making Nick the “other man” always looming over Clara and April’s friendship and the main impediment to their happiness. To accompany screenwriting duo’s ever piquant repartee, ably slung around with abandon by an exceptionally strong cast also including Jessica Hecht and Addison Riecke as April’s mother and saucy 13-year-old sister, respectively, “Banana Split” is punched up even more with surprisingly choice music selections ranging from Carly Rae Jensen to Kill Rock Stars tracks and zippy pacing, only amplifying the exhilaration Clara and April feel upon finding each other. By the time April has to finally pack up and prepare for college, she isn’t the only one who doesn’t want to leave with this delightful comedy every bit as wonderfully unexpected as the friendship that blooms at its center.

“Banana Split” does not yet have U.S. distribution. It will play once more at the L.A. Film Fest on September 25th at 9 pm at the Arclight Culver City.