Sherlock Holmes and the mysterious case of his 'killer' ancestor: Newly uncovered records show Benedict Cumberbatch's great-great uncle was tried for murder at 14 Henry Veltham, great-great uncle of Cumberbatch, tried for murder Crime dubbed The Romsey Stabbing Case happened in 1893 Farm-hand Henry accused of stabbing friend but was acquitted Mysterious case echos crimes unravelled by Cumberbatch in Sherlock "The Romsey Stabbing Case" sounds like it could be a Sherlock Holmes mystery. And in a way, it is. For the story comes from the past of the actor who plays the detective, Benedict Cumberbatch. Newly uncovered records have revealed that the actor's great-great maternal uncle Henry was tried for murder when he was only 14. Mysterious: While Benedict Cumberbatch (left) solves crimes in Sherlock, the case involving his great-great uncle is a mysterious blot on a family tree that includes Henry Carlton (right image, left), a naval commander Henry Ventham, a farm hand, was accused of stabbing to death his friend, Frederick Betteridge. The story appeared in the Hampshire Advertiser on Saturday, 18 November 1893, with the headline The Romsey Stabbing Case. It details how Henry was defended by a barrister called Bullen, the Recorder of Southampton, on the instructions of the judge, Mr Justice Hawkins. Henry and Frederick were out gathering nuts and blackberries one afternoon when it was thought they had an argument - and Frederick was stabbed. Cumberbatch's family history also includes Abraham, a slave-owner, and Benedict described his role as emancipation campaigner Pitt the Younger in Amazing Grace as an 'apology' for his ancestor Henry's story, supported by a third boy, was that there was no quarrel and that Frederick suddenly ran against him and the knife went into him. A jury accepted Henry's version that it was an accident and found him not guilty of both murder and manslaughter. The Hampshire Advertiser concluded its report with the comment: "His Lordship ... was quite content with the view they had taken of the case (applause in court)." The comment in brackets suggests the jury's verdict was a popular one. The intriguing story was unearthed by family history website, findmypast.co.uk. Cumberbatch, 37, who recently starred in Star Trek into Darkness, had a privileged upbringing and was educated at Harrow. On his father's side, he is descended from a prominent English family who were merchants and adventurers in the 18th and 19th centuries. His grandfather, Henry Carlton Cumberbatch, was a highly decorated naval commander who fought in both world wars. But Abraham Cumberbatch, Benedict's fifth great-grandfather, was a slave owner, who founded the family fortunes on a sugar plantation in Barbados. Today there are many Cumberbatches descended from slaves who took their name from the family which once owned them. In 2006, Cumberbatch starred in a film about the abolition of slavery called Amazing Grace. He described his role, as prime minister William Pitt the Younger, as a "sort of apology" for his ancestors. Debra Chatfield, a family historian from findmypast.co.uk, said: "Though Benedict's paternal ancestry is well known and documented online, this startling discovery is quite the revelation. It seems that there was a dark horse in Benedict's family tree, and while his great-great uncle was not convicted of murder or manslaughter, it shows us how many curve balls family history can throw at us.