Daniel Radcliffe broke down on 'Who Do You Think You Are?' while reading his great grandfather's suicide note.
Daniel Radcliffe
Samuel Gershon took his own life aged 42 following a 1936 robbery at his Hatton Garden jewellery business, but things got worse when police thought the Jewish businessman had faked the raid to claim on the insurance.
Speaking on the show, the 29-year-old star says: "Everything he had worked for and that his father had worked for, has sort of been destroyed.
"You want to just reach into the past and just go, 'Whatever you're going through, you have so much to offer the people who are around you still ... you have so much to give to them.
"And, they still would all have loved you.' "
Daniel was left shocked by a police report that said: "Jews are so frequently responsible for the bringing down of their own business premises," and the 'Harry Potter' actor admitted it was "jarring" hearing such comments.
According to The Sun newspaper's Bizarre TV column, he says: "There's a lot to dig into in that one sentence. It's very jarring to see being a Jew to be taken as a piece of evidence in itself."
What's more, Daniel is also expected to look into the story of his great-great-uncle Ernie, who fought at World War I, on the BBC genealogy show.
A source previously said: "When Daniel starred in TV drama 'My Boy Jack' - one of his first major roles after Potter - his inspiration was his great-great-uncle Ernie, who lost his life in World War I.
"As Daniel investigates exactly what happened to Ernie during the war, he discovers an extraordinary and moving cache of letters Ernie wrote home.
"He pieces together the heart-breaking story of how Ernie fought alongside his three brothers and how all of them, except for Ernie, survived."
Tagged in Daniel Radcliffe