Benedict Cumberbatch’s real-life parents also made a surprise cameo appearance as Sherlock’s mother and father.
The pair, who are both professional actors, played Holmes’ mother and father in a scene in Baker Street.
The actor admitted it was “nerve-wracking” appearing opposite his parents in the new series, but said he was also “so proud of them”.
He told the Press Association: “They’re Equity card carrying members but you know it was nerve-wracking because they are actors as well and yet they were brilliant and they were fantastic.”
His mother, actress Wanda Ventham, is best known for her role as Colonel Virginia Lake in the 1970’s sci-fi TV series UFO, and has also starred as Pamela Parry in Only Fools and Horses.
His father, actor Timothy Carlton, made a recent appearance as a judge in Downton Abbey, and has starred in a number of TV dramas including The Scarlet Pimpernel in 1982.
An average 9.2 million viewers watched the first episode of the third series of Sherlock last night, making it the most-watched episode of the drama so far.
The new episode offered fans several different versions of how the great detective faked the fall with one plan involving the help of guest star Derren Brown.
The Independent’s Ellen E Jones gave the first episode five stars, saying: “The greatest satisfaction of this thoroughly satisfying season opener was confirmation that Sherlock co-creator Mark Gatiss knows us fans better than we know ourselves.
“He dangled an easy answer to the fake death conundrum in front of us, then, just as we were realising that the outcome is never as good as the anticipation, he snatched it away again and replaced it with something better.”
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