More from Bruce Parry on BBC2 this evening (24th January, 9:00 - 10:00 pm). This time he spends time with a tribe in Gabon (Africa) and takes some serious hallucinogens in the name of Bwiti (the local religion):

"In a rite of passage that marks their transition to true manhood, the Babongo take a powerful hallucinogen that sends them on a life-threatening, three day trip.

Bruce prepares for the ritual by going hunting, collecting forest honey and getting to know his new friends.

When the Babongo judge that the time is right, Bruce is fed a tree root which induces hours of vomiting, and the visions that follow are memories of childhood and of people he had hurt in the past.

The rite ends with the tribe dancing with fire and encouraging Bruce to form meaning from the shapes he sees in the flames - leaving him exhausted but convinced that he'd undergone a valuable, life-changing experience."