The six-episode series will chart the stealthy game of undersea warfare from the greatest submarine campaigns of World War II. HELL BELOW profiles the strategic masterminds behind the brutal tactics of Nazi U-boats and reveals the extraordinary feats of Allied subs in the Atlantic and Pacific. HELL BELOW kicks off with THE WOLFPACK, as Hitler’s U-Boats begin their deadly combined attacks on Atlantic convoys in 1940. One of Germany’s top U-boat captains is pinned down in the North Atlantic, and realizes the vulnerability of attacking with a single submarine.