In 2023, Detective Hasan discovers a dead body in Longharvest Lane, Whitechapel — while in 1941 and 1890, two other detectives find the same corpse.

Hasan follows new leads in the present. As Hillinghead reluctantly closes his case, Whiteman goes to desperate lengths to hide involvement in his own.

Connections between the cases start to come into focus. Whiteman encounters an unexpected complication; Hillinghead attends a séance.

Hasan discovers she isn't the only detective investigating a murder on Longharvest Lane. In the past and future alike, relationships start to deepen.

The past, present and future collide as a set of fingerprints from 1890 are found in 2023. Maplewood uncovers the Commander's true identity.

On the day of the explosion, Hasan does everything in her power to help Elias make a life-altering choice. The others wrestle with their consciences.

Elias finally knows what it means to be loved. He creates the family he's always wanted — but Hillinghead has to suffer for it.

Across decades, the detectives work together to stop Elias from reshaping history. Will words be enough to break the loop and save thousands of lives?