The attempts of Prince Harry and Meghan Markle to move on may be in jeopardy due to an impending German documentary by seasoned royal reporter Ulrike Grunewald.

Grunewald and her crew have even gone to the Sussexes' hometown of Montecito, California, to speak with neighbors and learn more about their private lives. A source says the couple is concerned about what the "explosive" documentary may disclose, especially concerning Meghan's past before becoming a member of the Royal Family.

"They prefer to keep many aspects, especially concerning Meghan, private," the person said.

Before they ever met, Harry and Meghan both led active lives. Much about Meghan's past is still unknown, even though Harry has been very candid about many of his previous transgressions in his book. The program might go into her alleged argument with Kate Middleton, therefore undercutting the Sussexes' story that blamed Kate.

As of right now, Harry and Meghan are keen to move on from the past. Harry in particular may fear that disclosures about Meghan's history could jeopardise their newly discovered happiness.

The pair is nervous because they think the documentary will reveal previously undiscovered information about Meghan's life before becoming a princess. The approaching documentary heightens the tension in their wish for a new beginning as they work to start over.