(This might spoil some of the plot from Bridge of Spies, so Spoiler Warning!)
In Bridge of Spies, when the main character is on a train in Berlin, he sees people try to climb over the Berlin wall, but are shot down by patrols. At the conclusion of the story after he returns home, he is also on a train, and sees some children climb over a chain link fence, but they are not shot down.
What is the literary device to describe this change? The device seems significant because it shows a change by using two similar events that have different outcomes.