Berger was a cleric in the service of the Church in the 51st century.
He was one of the twenty clerics under the command of Father Octavian. They were investigating the crash of the Byzantium. Upon arriving on Alfava Metraxis, they realised they could not enter the ship to neutralise the Weeping Angel inside. They would be too close to the radiation spilling out of the ship. Berger was put in charge of laying explosives at the base of the cliff behind which lay an Aplan mortarium. Berger's team cleared a path into the mortarium. They stayed behind while the others went in with the Eleventh Doctor to find the Angel. Berger survived the incident with the time field. He helped rescue the Doctor, Amy Pond and River Song from the ship before leaving with his fellow clerics and River Song. (TV: The Time of Angels)