French soul singer Celine Dion has a long string of hit singles in her career, but surprised fans Saturday night with a cover version of perhaps the biggest hit single of the last decade, Adele's "Rilling in the Deep."  Check out some fan-filmed footage of the performance below.  Dion had been forced to cancel a string of dates earlier this year, but resumed her residency at the Caesar's Palace Colosseum in Vegas on Saturday night.