Belgium's Stromae brought in a fellow superstar from across the Atlantic, Kanye West, in a surprise Sunday on the final day of the Coachella festival. Stromae was performing his dance-and-song show at the festival in the southern California desert when West suddenly appeared -- to applause -- to join "Alors On Danse," a major hit in the French-speaking world in 2009 and 2010, according to numerous social media posts. While unannounced, the appearance had history to it as West previously recorded a hip-hop remix of "Alors On Danse" aimed at the North American market. Coachella, one of the most influential global music festivals, is well-known for its surprise appearances, although they have generally been more common in the first of the two weekends.