The film depicts the events of the Knockshinnoch Castle colliery disaster in September 1950 in which 135 men were trapped underground when mine workings flooded. Most were rescued but 13 men died.
Closing credits epilogue: To the Reserve Brigades who stand behind the miners all over the world.
The main star, John Gregson, does not appear until over half an hour into the film.
Opening credits: All characters and events in this film are fictitious. Any similarity to actual events or persons, living or dead,is purely coincidental.