On a Voice episode that aired in February, Riley became famous for having the fastest four-chair turnaround by judges in the show's history as he performed James Brown's "I Got You (I Feel Good)." After nailing an initial battle round, Riley became a frontrunner for season 8 winner.
On-screen, the 28-year-old singer was being mentored by judge Pharrell Williams, but in reality, he had already left the show the month before. After telling producers he needed to seek treatment for substance abuse, Riley told an interviewer that NBC had paid for his rehabilitation.
Riley, who wowed fans of the show with his delivery of classic R&B tunes, told Philly.com in late March that he had finished treatment and was working on an album -- just as Voice viewers learned of the singer's troubles.
The Voice host Carson Daly took to Instagram to share his heartbreak after learning of Riley's death. "It's a heartbreaking loss," Daly wrote. "He was incredibly talented and loved to sing. God Bless him."