A 90-second trailer for “Maleficent” — Disney’s film starring Angelina Jolie as Sleeping Beauty’s beguiling nemesis — aired during the Grammys on Jan. 26, set to Lana Del Rey’s subversive cover of the classic “Once Upon a Dream.” The trailer has since garnered more than 13 million YouTube views, and, in a promotional tie-in, the song became the fastest downloaded track in Google Play history.

The trailer was conceived by Disney’s senior marketing VP Jackson George, who showed music president Mitchell Leib two versions: one traditional and very “Disney,” says Leib, the other a “moody piece with the song from ‘Sleeping Beauty’ turned into a twisted children’s nursery rhyme — like a horror film.”

Leib loved the latter spot, and envisioned Del Rey performing a polished version of the song. The Grammy-nominated singer — whose haunting “Young and Beautiful” became the signature refrain for last year’s “Great Gatsby” soundtrack — jumped on the idea and churned out a near-complete “demo” in four days (performing the finished vocal over only a single note and click track).

The original song, by Jack Lawrence and Sammy Fain from Tchaikovsky’s melody, “was such a happy, upbeat, skipping-in-the-fields track,” says producer Daniel Heath, who conceived the arrangement. “It was hard to make it dark and spooky.” Heath flew to London where the film’s score was being recorded, borrowing composer James Newton Howard’s orchestra and boys’ choir to flesh out his cinematic production.

Google Play was given a sneak peek of the trailer, and partnered with Disney to do a free download promotion of the song for nine days — resulting in 352,000 download s, and fueled a sales spike in Del Rey’s other material.

“It’s kind of a miracle,” says Leib, “because when the spot ran during the Grammys, the card at the end that says, ‘Go to Google Play for a free download’ wasn’t up there for half a second.” The fact that Del Rey’s vocals seem to emanate from Maleficent herself was completely unintentional serendipity.

“It’s magical working with Lana,” says Heath, “because everything just tends to align.”

The song will be heard over the film’s end credits and on the soundtrack album to be released May 27. Del Rey is also working on remixes. “Lana has a very unique vocal presence,” Leib says. “It’s deep, articulate, patient. … She’s not a faint little pop artist — and we do a lot of that at Disney, to be honest. We were trying to bring some gravity and artistry to this. It just felt like great casting.”