One of the benefits of being an occasional insomniac is the opportunity to catch a Sam Fuller film at 2 AM on TV.
This felt like a vehicle to showcase 20th century Fox's Cinemascope process, stereophonic sound and Bella Darvi - a Darryl & Virginia Zanuck pet project supposedly meant to be the next Ingrid Bergman - described by Widmark's Capt. Jones as "a child prodigy with a body by Fisher."
Widmark is enjoyable enough, but he isn't given much to work with in terms of script. The dialogue is pulpy as one would expect from Fuller, and there are some brief moments of tension with the submarines playing hide & seek.
A couple of Fuller regulars are found here: an unfortunately underused Gene Evans & Richard Loo - pretty sure I saw Richard Monahan in there as well (Pvt. Baldy from The Steel Helmet).
I would recommend this to hardcore fans of Widmark, Fuller, and people with nothing better to do in the wee hours, but it isn't anything memorable.
ETA: that was Neyle Morrow I saw, not Monahan.