On the final lap of his book tour last March, Prince Harry sat in a comfy armchair on a living room set with a fire crackling in the background. Opposite him sat best-selling trauma expert, Dr. Gabor Maté.

Maté, 79, a Hungarian Canadian primary care doctor whose maternal grandparents were murdered in Auschwitz, argues that psychological problems and even psychotic illness often stem from childhood trauma. His 2010 book, In the Realm of Hungry Ghosts: Close Encounters with Addiction, turned him into a “late-in-life literary juggernaut.” He is now so in demand, his website states “he has to be booked years in advance.”

But, at this moment, Maté was training his gaze on the prince for an impromptu diagnostic session. Viewers paid $33 a ticket, which included a copy of Harry’s new memoir, Spare, to watch the live-streamed “intimate conversation.”