The Hirogen turn Voyager into a holodeck war.
The Hirogen have taken over Voyager and are running the crew through holodeck programs as prey, with neural interfaces convincing them they are their characters. One scenario is a recreation of Nazi-occupied France in 1944, in which Janeway runs a restaurant as Katrine, a Resistance leader, alongside Tuvok as her barman and Seven of Nine as a singer, while the Hirogen play the German occupiers. Another program pits the crew against each other as Klingon warriors, and the Doctor must keep treating the injured crew so the hunts can go on.
The Doctor and Harry Kim free Janeway and Seven from their interfaces, and they plan to break the Hirogen's hold on the ship. As American troops led by Chakotay and Tom Paris attack the town, an artillery strike blows open the holodeck walls, and the war spills out into Voyager's corridors. The fourth-season two-parter is a big action story that puts the main cast in period roles.