On Christmas Eve 1953 a volcanic eruption caused a massive lahar to flow down Whangaehu River. When the Wellington-Auckland express crossed the rail bridge at Tangiwai minutes later, it collapsed and carriages plunged into the flooded river. 151 people died out of 285, in NZ's worst rail accident. This 2002 documentary examines events and the board of inquiry finding that the accident was an act of God. This excerpt demolishes the story that Cyril Ellis could have warned the train driver what lay ahead, and argues there was a railways department cover-up at the board of inquiry.