The part I'm referring to specifically is the concept of The Knot, the two timelines that were dependent on time travelers from each other to make the changes t

The part I'm referring to specifically is the concept of The Knot, the two timelines that were dependent on time travelers from each other to make the changes that caused them to exist. Of course the show ended with eliminating The Knott, leaving the only paradox as being where two people suddenly materialized in the middle of the road from to warn about a bridge being out before just as mysteriously ceasing to exist.