No, we're not joking...
And now we've got the first official photos of the A/Z-listers taking part.
There's TOWIE star Lucy Mecklenburgh. Not bad, eh?
Oh and Sarah Harding. And don't forget H from Steps - he'll be tumbling around too. Plus a bunch of other people.
But we've got some bad news... Mr Motivator was supposed to be taking part. But alas, during rehearsals Mr Motivator - real name Derrick Evans - sustained a bad knee injury.
WHY GOD, WHY?
The judging panel will be made up of Olympic gymnastics legend Nadia Comaneci, London 2012 heartthrob and Strictly Come Dancing champion Louis Smith, Team GB gymnastics captain turned sports broadcaster Craig Heap, and cirque artist Sebastien Stella.
And it will be prsented by Alex Jones, with Beth Tweddle giving a helping hand.
Tumble will see the famous folk attempting to learn and master gymnastic skills across six weeks of live TV shows. The challenges will include tumbling (obvs), double trapeze, acrobatic gymnastics and trampolining.
BBC Commissioning Executive Rachel Ashdown said: "These celebrities are embarking on a gruelling training regime combining aerial and gymnastic skills.
"They'll use them all to deliver breath-taking performances that you'd expect from the department that also produces Strictly Come Dancing."
Tumble will air on BBC One from 9 August.