In BCS, we see bits of Saul's present-day life, but the real interesting story is a prequel. We know roughly how it all plays out, but the specifics of his life are the fascinating parts.
In Assassin's Creed, we see bits of Desmond Mile's present-day life, but the real game takes place in the genetic memory past-lives. We know roughly how this alt-history plays out, but the specifics of it and the worldbuilding are the interesting parts.
I stopped playing the games in 2013 after I realized, like, Christ, a new game each year? Wait, two new games this year? I can't keep up with that.