The Wild Wild West - Season 3 Episode 2 The Night of the Firebrand

On a mission for President Grant, agent West travels to Fort Savage to meet with a Major Jason and help prevent a revoloution in Canada that outlaw Shawn O'Riley has plans to incite. At the fort, West reads a description of O'Riley and realizes too late his striking resemblance to Major Jason. O'Riley announces that he now controls the fort and is holding the real major and his men captive. Meanwhile, Gordon has gone under cover to learn the details of the revolution. He arrives at West's side just as his partner is trapped on wrong side of O'Riley's gun.