The Twilight Zone (1959)

S5E10 The 7th Is Made Up of Phantoms

A contemporary National Guard unit unexpectedly finds themselves transported back in time, right in the midst of Custer's Last Stand during the Battle of Little Big Horn. Struggling to comprehend their unusual situation, they must navigate the chaos of the historic battle while trying to avoid altering the course of history. As they face the challenges of combat and survival, the soldiers learn valuable lessons about bravery, sacrifice, and the complexities of the past.