Rap superstar Eminem made his long-awaited return Friday with a strikingly fresh sound -- an introspective ballad that features Beyonce.

Eminem, the top-selling rapper of all time who earned his fame on the back of aggressive beats and lightning-quick rhymes, is accompanied almost entirely by piano and strings on the new track, "Walk on Water."

In a series of social media posts, the 45-year-old indUS rapper Eminemicated that "Walk on Water" was the debut single of a new album, "Revival," which would be his first in four years.

Eminem gave no further indication on the release date. MTV simultaneously announced that Eminem would perform "Walk on Water" live for the first time Sunday at the network's European Music Awards in London.

"Walk on Water" is driven by a Gospel-tinged chorus in which Beyonce sings of how Eminem -- earlier the self-described "Rap God" -- was deeply human.

"I walk on water -- but only when it freezes," sings Beyonce, in one of her first appearances since giving birth to twins in June.

In the song Eminem describes his perfectionism and how it fuels his anxiety as he fears his new material will not live up to his standards.

"Will this just be another misstep / To tarnish whatever legacy, love or respect I've garnered?" he raps.

"The rhyme has to be perfect / The delivery flawless / And it always feels like I'm hitting the mark / 'Til I go sit in the car, listen and pick it apart."

Eminem name-checks legendary late artists including Prince, Tupac Shakur and The Notorious B.I.G. and declares himself to be in a lesser league.

The song only hits an older hip-hop sound in its last moments when, in a sarcastic flash of his old self, Eminem alludes to "Stan," his mega-hit from 2000.

Eminem first emerged from a year of quiet last month when he delivered an angry freestyle accusing President Donald Trump of bigotry and incompetence in a video aired at the BET Hip Hop Awards.

Eminem, a white Midwesterner whose listener base likely includes many voters for Trump, demanded that his fans choose him or the president, of whom he said: "Racism's the only thing he's fantastic for."

Souece: AFP