When the Americans were finally self-interested enough to join WW2, they needed a lot of boots on the ground, and some in the air, and a few if by sea.

Captain Krause (Tom Hanks) is in command of an escort force protecting an Atlantic convoy consisting of 37 Allied ships on their way to Liverpool. They’re passing through the Mid-Atlantic gap, so called because no antisubmarine aircraft are able to reach them. They’re on their own. Still three days out of range from protective air cover, they intercept German transmissions. It is likely U-boats are near. This is merely the start of 13 back to back covers (or 52 hours) on the Greyhound’s bridge as Krause fights to save his ship, protect those in his convoy, and rescue those who succumb.

As a war movie, director Aaron Schneider makes very effective use of his 90 minute runtime, keeping the focus on a very intense combat. It’s basically a race against time, a fight for survival until they reach precious, essential air cover once again.

But the reason Greyhound really shines, as did its source material, The Good Shepherd by C. S. Forester, is in its fascinating and intricate character study of the man behind the wheel. Captain Krause has been a career Navy officer for many years. His seniority is unquestionable, but in truth, this is his first wartime mission. The other captains are younger and junior to him in rank, but they’ve been at war for two years already. Although we see him act in competent and level-headed ways, we are also privy to his self-doubt. The combat is relentless as the minutes and hours tick by, Krause unwilling to leave his post, and only the kindness of a mess attendant (Rob Morgan) ensures he doesn’t go hungry.

Hanks adapted the material himself, and though we never see the guy make an acting misstep, he is clearly suited to this character, slipping on the captain’s skin as if it were a comfortable, monogrammed slipper. You feel his fatigue, and inklings of inferiority, but with the weight and fate of an entire fleet on his shoulders, he never gives less than his best. The constant danger is exhausting, the many snap judgments that must be made while in command are overwhelming, and above all, we see Krause struggle with his conscience – muttered prayers for the souls on board, but also a refusal to celebrate enemy kills, a necessary part of war perhaps, but one with which Krause is not entirely comfortable. It’s a facet rarely explored in war movies and Hanks is up for its portrayal, but cleverly, the points are merely plotted, the lines themselves drawn by the audience.

I expect nothing less that complete satisfaction from the material Hanks is choosing, and he’s so unvaryingly good it’d be almost tedious if it wasn’t so wonderful. And this, too, is wonderful, and not even annoyingly so. Hanks truly is a master and Forester’s carefully observed novel cannot be over-rated.