However, it turns out there’s more to his Radio 1 no-show than we first thought.
Since taking over as host of the breakfast show, Greg has become well-known for his elaborate pranks and stunts, and it turns out his absence on Wednesday was part of one.
Posting on Twitter on Wednesday afternoon, he explained to his Twitter followers that he’d been “captured” at a Brits afterparty.
“Some explaining has got to be done,” he said. “Last night, at the Brits afterparty, I was put into a car, blindfolded and driven over an hour or so away to a building which contains this white room.
“The only thing I was being told is that I was being taken to the boss’ place.”
Greg then assured his followers that he was “as in the dark” as everybody else over his whereabouts, revealing: “I’ve since learned that it’s a thing called Who’s Got Greg?
“This requires you to be the detectives and with me, work out who from the Brits captured me and took me here. [If we] work that out, I can escape, so please help me.”
Many fans have pointed out that the room Greg is in appears to have been padlocked from the inside, with the presenter later revealing: “For all those mentioning the padlock on the inside…It has a code that I imagine I have to solve (with your help) in order to get out and see who my captor is…”
He also tweeted out a mysterious letter, which was hidden inside a table:
The matter was also discussed on The One Show, as hosts Matt Baker and Alex Jones urged viewers to get involved in cracking the code:
On Thursday morning, as Greg found himself still locked in the room, the BBC tweeted a round-up of the clues so far, with a “red scarf” seemingly playing an important role:
Greg said: ”[This] feels slightly nightmarish. The thing is, there’s a lot to go at and so many brains on this all over the world really that somebody will come up with this and that’s what I need.
“I need theories and to really think about all the bits. It is fun but ultimately I do want to get out of here ASAP. I’m just lying here in pants. It’s bleak.”
Among the popular theories about the mysterious “boss” include The 1975 frontman Matty Healy, due to a song the band released the morning after the Brits referencing running into someone called “Greg” at a birthday party.
Others have speculated that it’s actually Mollie King, pointing out that the singer-turned-presenter sported a key on her dress at the Brit Awards.
The clue regarding Lizzo’s “spill” also seems to point in Harry Styles’ direction, after the singer accidentally poured red wine on him during a segment in this year’s Brits.
Around this time last year, Greg was involved in an elaborate escape room stunt, which took him more than a full day to get out of.