“Greyhound” (***1/2 out of four) was a white-knuckle action melodrama set early in WWII in which an inexperienced U.S. Navy captain (Tom Hanks) must lead an allied convoy on the Greyhound submarine but they find themselves in treacherous waters when they begin being stalked and terrorized by Nazi U-boats and have to outsmart and outbattle them in order to survive. Hold on tight! A rock-solid dramatization of war on the high seas with particular kudos to Shelly Johnson’s magnificent cinematography, Blake Neely’s stirring (and scary) music score, Mark Czyzewski and Sidney Wolinsky’s razor-sharp editing, and Aaron Schneider’s tense and swift direction. Hanks is solid as an oak as usual in a role similar to “Saving Private Ryan” and “Captain Phillips.”