Adele's "Hello" has been reworked countless times since its release last October.
But this eerie cello mash-up with Mozart's Requiem "Lacrimosa" is undoubtedly one of the most haunting interpretations yet.
Musical group The Piano Guys posted its stunning rendition of the English singer's global smash hit to YouTube Thursday, and it's now going viral:
The group, from Saint George, Utah, said its take on the track was "a musical experiment bridging 18th century spiritualism and 21st century secularism."
Despite their name, The Piano Guys only uses electric and acoustic cellos in this song.
"Imagine Mozart and Adele in the same room in an intense co-write session, quill and pen in hand, respectively," the group wrote in the video's description.
"Picturing this hypothetical hangout helped to spark the creative combination of the two."
Here's Adele's original version:
The group selected the two tunes because, despite being admittedly different, they shared the same fundamental feeling. Mozart's song bemoans spiritual death while Adele's is about relationship regrets.
"Different centuries. Different realms. Same emotion. Perhaps we aren't as far from our predecessors as we think we are," the group added.
Listen to Mozart's Requiem "Lacrimosa" here:
Adele's song has already been parodied by Miss Piggy and Kermit, stressed-out moms and in a broadcast news style. It's also been transformed into an ode to junk food cravings and covered by dozens of other artists across the world. The "Hello" music video smashed the 1 billion mark on YouTube in just 87 days.
The Piano Guys have a history of mashing up pop songs, including this beautiful Scottish reworking of Rachel Platten's "Fight Song".
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