I know it isn't a film....
From NRK...Excellent rail videography and before and after dissolves (most countries other than the US seem to make better railroad documentaries).
Link: Arendalsbanen - A Journey of 100 Years
Some 'well qualified' engineers are on the train.
At 14:15, the 97 year old engineer riding in the cab explains that at one time just past the powerhouse he hit a horse that was on the rails.
Just ran across the above video yesterday from another (Swedish) rail forum I frequent.
Shameless plug:
Link: Postvagnen
-K