I have a faint memory of either an action film or tv series I watched in the early 80's (or possibly late 70s) as a child. The main character was a woman who pretended to be blind to find out information. I think she was trying to discover the whereabouts of her kidnapped children as the last part she rescued them from some hideaway under the sea? I just remember it was so good but can't remember its name and google isn't helping out :)