Based upon the French film Le Jour Se Lève, The Long Night opens in the in the midst of a dire situation: ex-serviceman Joe Adams (Henry Fonda) finds himself holed up in his apartment, surrounded by policemen who soon open fire in a relentless and determined manner. Adams has been accused of murder, and as his apartment is riddled with bullets, he flashes back to how this all came about. It began when Adams met Jo Ann (Barbara Bel Geddes), who, it turns out, grew up in the same orphanage at the same time as he. They soon fall in love, but things are complicated when a magician named Maximilian (Vincent Price) enters the picture. He tells Adams that he is Jo Ann's father, but that he doesn't want her to know this. Maximilian begins spending a lot of time with Jo Ann, which makes Adams feel vaguely unsettled. He discovers that Maximilian lied -- that he is not her father but is someone who has been trying to seduce her for a long time. Maximilian goes to Adams' apartment to taunt him, with the result that Adams shoots him, thus bringing about the current state of affairs. As Adams has been recalling all of this, a crowd has gathered, including Jo Ann. She leads the crowd in protesting the police's actions, and a riot brews. With tension continuing to rise, Jo Ann desperately tries to find a way to rescue the man she loves.
~ Craig Butler, All Movie Guide