Thailand’s royal family are officially revered and protected by harsh laws, which can land you in jail for many years.
But over the past five months a student-led protest movement has started demanding reform of the monarchy, and an end to military coups. Thailand has had 20 in modern times.
The protesters want King Vajiralongkorn’s power and spending to be limited, though many Thais remain strongly loyal to him and object to the reform campaign.
BBC’s South East Asia correspondent Jonathan Head reports from Bangkok.
Filmed and edited by Nikki Millard.