Secret sets are one of the features which make Glastonbury so special and ticket-holders have been busy speculating who might be performing unannounced this year.
There will be lots of people keeping their fingers crossed that Oxford indie-rockers Foals are set to perform at the festival, as has been heavily rumoured, while a number of other top acts have also been namechecked.
Now a huge hint has just been dropped that American pop sensation Lady Gaga and Hollywood actor Bradly Cooper could be set to make a surprise appearance together.
BBC Radio 1 DJ Edith Bowman may have accidentally let the cat out of the bag this morning when she featured on Channel 4's Sunday Brunch.
She said she knew of one secret set when pushed to reveal more by presenters Tim Lovejoy and Simon Rimmer.
She said: "I may know one, I can't possibly say.
"On my podcast I had Bradley Cooper talking about A Star is Born, and when I spoke to him I was like 'I just want to see you guys do a gig, you know play it live'.
"He was like 'well we have been talking to Nick (Dewey) and Emily Eavis about it, we'd do the Park Stage' and I said 'that would be amazing!' Bradley Cooper and Gaga doing the Park Stage."
The band which acted as Bradley Cooper's backing band in the film, Lukas Nelson & Promise Of The Real, already have a set on The Park Stage at 3.15pm on the Friday, for an hour - so perhaps there could be a few familiar faces cropping up.
There are two TBA slots on the Park Stage, one at 11.30am to 12.10pm on the Saturday and one at 6.15pm to 7.15pm.
A Star is Born was released in October 2018 and stars both Bradley Cooper and Lady Gaga.
Last year, Cooper revealed his love for the festival and said he was 'in talks' to perform next year, so it definitely isn't beyond the realms of possibility.
