My Marianne

In the Netflix movie "Eurovision Song Contest: The Story Of Fire Saga" the role of "Sigrit Ericksdóttir" was played by actress [a=Rachel McAdams], but the artist/voice behind the songs is actually Molly Sandén (full name Molly My Marianne Sandén), who McAdams lipsynced to. [a=Will Ferrell] (the other lead role of the movie) on the other hand performed his vocals himself.

From a [url=https://www.vanityfair.com/hollywood/2020/06/eurovision-netflix-rachel-mcadams-singing]Vanity Fair article[/url]:

According to Netflix, Sandén’s vocals were mixed with McAdams’s own voice for the tracks. In a separate phone call with Vanity Fair, Eurovision’s music producer Kotecha said that Sandén and McAdams’s “tones worked so well together” that, in playing back certain tracks, he had a hard time differentiating between the vocals. But Sandén, who has seen the film, said she only noticed McAdams’s voice in a scene in which the actor was singing to herself in front of a piano. Asked if she thought the vocals had been mixed, Sandén sounded skeptical: “If they say so, maybe that’s the truth. But I just know that I didn’t really hear [McAdams] in the soundtrack...maybe it’s mixed in somewhere.”