A bizarre anomaly opens up in an abandoned prison. When a tourist goes missing, the team is sent to investigate, only to encounter an old friend.
- The Bus Came Back: Danny finally comes back after spending some time back in the Pliocene.
- Death Glare: Danny gives a suspicious version of this to Phillip, as his name was referenced several times in Helen Cutter's journal.
- Feathered Fiend: This episode features the return of the Terror Bird. However, it's presumed to be a different species than the ones that showed up in Series 3, due to being a different color.
- Gone Mad From The Isolation: This is stated to be the reason for Patrick's poor mental state. He was stranded in the future by himself for many years, at the mercy of countless Camouflage Beasts.
- Oh, Crap!: Connor does some research on the splintered anomaly. He learns that very soon, an event known as "Convergence" will happen, in which countless anomalies are going to open all at once, all over the world.
- Put on a Bus: After finally getting back to the present, Danny leaves through the anomaly to chase down Patrick. Emily also leaves, going back through an anomaly to her own time period.
- The Reveal: Ethan Dobrowski is actually Patrick Quinn, Danny's little brother who was presumed dead eighteen years prior. He disappeared through an anomaly into the future, and eventually took on a new identity before joining up with the Time Tribe.
