Home is Where the Hearth Is

After inheriting his eccentric grandmother's crumbling cottage, a cynical big-city architect discovers that the enormous, soot-caked fireplace—the "hearth"—is actually the camouflaged housing for a still-functional, WWII-era spy robot that believes WWII is still on, and that its new "operator" (the architect) is a deep-cover agent whose mission is to save the village from a suspected Nazi sleeper cell (the local knitting circle).