Sebastian Stan was 27 in Captain America: The First Avenger when he played the character 'James Buchanan 'Bucky' Barnes'.
That was over 13 years ago in 2011.
Today he is 41, and has starred in 44 movies in total, 29 of those since Captain America: The First Avenger was released.
In Captain America: The First Avenger, I think Sebastian Stan looks: