Disguised as a German soldier for an underground mission, Sgt. Carter is caught by an enemy Panzer division. At the behest of Hogan, Carter continues his masquerade in order to recover a cache of confiscated dynamite before the real Germans can find the explosives. Dave Willock appears as an American captain, while Hogan's Heroes general-purpose actor Dave Morick is cast as a sergeant. Written by Laurence Marks, "One Army at a Time" originally aired on February 13, 1970. ~ Hal Erickson, Rovi