Submarine movie are a sub-genre in themselves (no wordplay pun intended) and the appeal is easy to appreciate, boys-own (and usually boys only) adventures in which the characters can be isolated from the outside world and at least once during the course of the movie get trapped and threatened by the very ocean they travel through. The 1975 Gray Lady Down is as much a part of the 1970s disaster movie cycle as it is a traditional submarine caper and is of principal interest for its cast of the moment, which includes Charlton Heston, David Carradine, Stacy Keach, Ned Beatty, Ronny Cox, John Carpenter regular Charles Cyphers and, making his film debut, Christopher Reeve.

Sixty miles off the coast of Connecticut, the USS Neptune, a US Navy nuclear submarine returning from routine manoeuvres, surfaces in thick fog and is involved in a collision with a Norwegian cargo ship. The resulting damage leaves the sub sunk, partly flooded and precariously balanced on the edge of a deep ocean canyon. In charge of the 41 surviving crew members, many of whom are seriously injured, is Captain Paul Blanchard (Heston), on his last tour of duty before retirement.

Back on the surface, a Navy rescue team, led by Captain Bennett (Keach), has already been alerted and is in attendance at the scene awaiting the imminent arrival of a Deep Submergence Rescue Vehicle (DSRV), a vehicle specially designed for rescuing submarine crews from such disasters. However, the Neptune's desperate situation worsens dramatically when an underwater landslide covers its escape hatch with debris, making the DSRV's rescue attempt impossible. As the time ticks away, Blanchard and his crew face a triple threat – their oxygen supply is rapidly running low, the water pressure is threatening to crush the Neptune's hull and the sub is also at risk of slipping off the ledge and into the bottomless abyss. With no other options left, the only hope for survival for Blanchard and his men comes in the form of a pair of misfit seaman, Gates (Carradine) and Mickey (Beatty), and their experiment submersible known as the Snark.

Gray Lady Down will be released on UK DVD by Fremantle Home Entertainment on 27th October 2008 at the budget price of £7.99. Don't expect more than the movie, but previous budget Fremantle releases suggest the aspect ratio should – and that's an unconfirmed guess – be the correct scope ratio.