Nelly paid a visit to music’s resident doctor, Dr. Dre. The St. Louis rapper hit the studio for a late-night recording session with the West Coast icon on Monday, tweeting a photo from the lab.

“WOW in studio wit the legend dairy @drdre,” shared Nelly, who released his mixtape O.E.MO on Christmas Eve.

Nelly is working on the follow-up to 2010’s 5.0. Meanwhile, Coachella headliner Dre has decided to take a break from recording his long-awaited Detox.