The decision to bring Mosab Hassan Yousef's book, Son of Hamas to the screen can't have been an easy one. Least of all for Mosab. Coming out in a paperback as an Israeli spy when your father is a radical Palestinian liberation leader is questionable, but to narrate his own story on camera seems like the act of a mad man with a death wish. Mosab isn't mad, but after sharing 99 minutes of screen-time with Gonen Ben Yitzhak, the Shin Bet handler who recruited and trained him, I wasn't sure who he really is or why he danced with the enemy only to be ostracised by the family he claims to love.

Interestingly, Mosab reveals that his father Sheikh Hassan Yousef, who was imprisoned by the Israelis, did not raise him to hate; yet he instinctively embraced militancy and was arrested for purchasing illegal weapons and imprisoned.

Prison proved to be the game changer for director Nadav Schirman's hero, as it was there that he witnessed his so-called kinsmen torturing - often to death -other Hamas prisoners suspected of betrayal.

Questioning the cause was a sign Gonen Ben Yitzhak was trained to spot in a potential collaborator, but to hook the son of a Hamas leader was a counter-intelligence hole in one. As in Homeland or any post 9/11 terrorist thriller, it is the details that fascinate and The Green Prince is at its best when Gonen describes the psychological grooming of his recruit according to Shin Bet's confidential rules.

With double Oscar-winning British producer Simon Chinn at the helm, The Green Prince scored at Sundance and will continue to pick up plaudits if only for its story, which would be dismissed as far-fetched if it were a fictional drama. As a talking heads doc it is intriguing, but not as memorable as it should be considering Mosab's sacrifice.