After the events of Avengers: Endgame, Steve used the Pym particles to put all the infinity stones back in their correct places in space in time. But, he decided to go back to the love of his life, Peggy Carter, in the 1940s. What happens when he realises he can do good? Instead of living out the suburban dream, Steve decided to do what he can to save his best friend. He was going to fix things.