WHAT has Adam Levine done to his beautiful hair?

Adam Levine was once voted the Sexiest Man Alive, but we have a feeling he'll be waiting a while to win that award again… unless his hair can grow at superhuman speed.

The Maroon 5 frontman is known for his perfectly styled dark locks, but he said bye-bye to the quiff this week and did the unthinkable. Posting a selfie to Instagram this morning, Adam revealed he had shaved all his hair off:

It seems we're not the only ones who got a shock when we saw Adam's barely-there do, as his wife of one year Behati Prinsloo didn't look all that happy either. "She's into me… I think…" Adam wrote, sharing a picture of himself and Behati lying beside each other.

This isn't the first time Adam has changed up his hairstyle, but it's definitely the most extreme look we've seen. Back in 2012 the singer went for a short buzzcut, saying he considered a head shave "an emotional reboot.”

Behati was even left in charge of his look a few months ago, going for a shaved-sides-and-quiff style:

We somehow doubt she was the mastermind behind the full head shave, though…