From the YouTube video summary:

The 1500+ inmates of Cebu Provincial Detention and Rehabilitation Center in Cebu City, Philippines, do a lot more than just languish in a cell. They have livelihood programs and personal savings accounts, allowing them to earn and save money for legal fees or the families they left behind. Perhaps even more impressive is what they do with the rest of their time: rehearse and perform elaborate parodies and dance numbers, like the recreation of Michael Jackson's "Thriller" seen here.