How hilarious ‘Barbie’ earworm ‘I’m Just Ken’ brings toxic masculinity to its knees

“Barbie’s” entire narrative builds, of all things, to a musical number.

Part power ballad, part battle sequence and part dream ballet, “I’m Just Ken” arrives onscreen like an elaborate bit, or an excuse for Ryan Gosling to flex his Oscar-nominated vocal cords and reprise his viral dance routines. And yet it’s an absolute showstopper, one as ridiculous as it is ideologically ambitious and visually astute. Like the powerful monologue America Ferrera delivers about the impossibilities of being a woman, this five-minute sequence is an empathetic acknowledgment of the pressures put on men to (literally) perform their masculinity, often to toxic lengths.

Packed with clever jokes, film references and social commentary, the number might seem like wildly misguided chaos. (In theater terms, it’s as if the princes of “Into the Woods” were performing the “Les Misérables’’ battle anthem “One Day More” before a “West Side Story” rumble on that “Mamma Mia! Here We Go