This movie is superb but chilling. Set in 1950s Poland when the Communist Party was attempting to eradicate religious practise, the story centres around a young man who is tasked with firstly surveilling and then defaming key Catholic clergy. We watch him transform from an idealistic, ambitious youth into an obsessive zealot. It's fascinating and quite shocking to witness not only the lengths he'll go to to achieve his goals, but also his resulting moral decline. Equally shocking is the effect he has on others. I don't know whether the movie depicts true events but the inclusion of what looks like some actual historical footage from that time certainly adds to the authenticity - and to the impact. Well written and exquisitely photographed it held my attention throughout. Highly recommended particularly for those interested in historical dramas.