Complete story — includes the ending
The alternate Fringe team tracks the shapeshifters to a revived David Robert Jones, who survived the universe crossing with Peter's erasure from time. After they capture him, he initiates several terrorist attacks until he is released. After being released, he disappears only to appear in the prime universe to steal a rare mineral, 'Amphilicite', only to cross back to the parallel universe and disappear. In the wake of Jones' escape, the two universes agree to work together to defeat Jones and his army.
Sources and content license
Source and revision history · Adapted from Wikipedia contributors, Fringe season 4. HTML formatting and reference markers removed. · Content license