Photo credit: Splash News
... but the secret wasn't a secret for long, Mimi and Nick surfaced at the Narita International Airport:
Photo credit: Wireimage
Apparently Mimi has made her way to the Land of the Rising Sun in order to throw out the ceremonial first pitch at the Yomiuri Giants vs. Rakuten Eagles match at Tokyo Dome on May 28:
American singer Mariah Carey, 38, will throw out the opening pitch at the Yomiuri Giants v Rakuten Eagles match at Tokyo Dome on May 28. NTV said Carey will take part in the ceremony to promote her new album "E=MC²" from which the network's baseball telecast theme song "Lovin' you long time" comes.
I would hope that Mimi is in town for more than just a baseball game. In any event, much congrats and felicitations go out to Mimi and Nick on successfully remaining married for a solid month! Congrats!!! [Source]