Complex sentence: The'friend' would be a trained improvisational comedian, who would progressively torment the contestant, and the friends and loved ones of the contestant, who, in turn, were unaware of the folie à deux.
Split into simpler sentences: The'friend' would be a trained improvisational comedian, who would progressively torment the contestant, and their friends and loved ones. The catch was that the friends and family of the contestant were unaware of the folie à deux.