K129

[Wallfire]

I remember reading about this some time ago, but it was very hard to filter out what is true and what has been "added" to make it more interesting. The story I read was that the command codes on the subs were not enough to fire the missiles but and extra codes need to be sent to the sub. No one on the subs knew about the extra code. If the extra code was not entered and the missiles were fired they would self destruct but not the war heads.  
When I look at the video the film Phantom comes to mind, wonder if he copied the idea.

https://www.imdb.com/title/tt1922685/