Kim Kardashian and Kris Humphries are not kidding around about this wedding! The two were spotted Thursday heading into 3rd Street Dance Studio in LA -- perhaps for some lessons for their first dance together, and they met up with Mark Ballas!

The couple went into the studio in one set of clothes and left in another ... maybe they worked up a sweat with some snazzy steps!

Kim was paired with Mark on Season 7 of Dancing With the Stars, and they rehearsed at the same studio while competing. The two were spotted catching up over dinner Monday night. Mark would be the perfect person to choreograph Kim and Kris' first routine!

The couple has already registered for gifts. Kim recently told X17 exclusively of making the wedding happen fast, "When you're ready, you're ready."

Check out more pics of the trio after the jump and in our gallery below!