- You may be looking for Water's Edge.
Later, as the train is passing over a bridge, the bridge collapses due to flood waters and the engine and first six cars fall into the water, including the car carrying Matiu and the Doctor.
When the Doctor and Matiu escape from their car, they help in the rescue efforts. Matiu explains that he came here, into the past, to find out what became of his grandfather Hemi, who disappeared before Matiu was born.
As they continue to work, Matiu ends up working alongside a young man named "Jim", who he eventually realises is his grandfather Hemi. They find a young girl trapped in one of the half-submerged cars, and as they try to rescue her, something large slams against the car. In order to save the lives of Matiu and the girl, Hemi lets himself be swept away.
Matiu wakes in the community hall. An army nurse tells him that the young girl is all right but doesn't know who rescued her and Matiu. When the Doctor finds Matiu, Matiu realises it was he who saved them.
Matiu returns home.
- The Doctor is wearing his blue patchwork coat.
- At the conclusion of this story, a note states that the train disaster was a true event, though the characters in the story are fictional.
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