'Restless legs syndrome' (RLS) is a condition of the nervous system that, in its most serious form, can be highly debilitating. It is thought to affect roughly 10 percent of people worldwide, so how come it is still relatively unknown and poorly understood?
BBC Reel's Howard Timberlake goes in search of some facts and discovers that the condition, and some of the medication used to treat it, throws up more questions than it does answers.