Arnon Nampa

He may have an unassuming demeanor and a penchant for dressing up like Harry Potter, but human-rights lawyer Arnon Nampa has his country’s establishment quaking. Thailand is the United States’ oldest ally in Asia and has served as a bulwark against more authoritarian neighbors, but its democracy has eroded as ties with China blossom.

Arnon has energized young Thais with his demands to strip political power from the historically sacrosanct royal family and shred the military-drafted constitution. As a result, he has been arrested three times in recent months and charged with sedition. But as COVID-19 continues to impact Thailand’s tourism-reliant economy, more young people are joining demonstrations that are already the biggest since the 2014 coup d’état—which experts say is pressuring the military-led government into a corner. “People are sick and tired of living under a repressive regime,” he told TIME late last year. —Charlie Campbell