BBC Louise Brealey plays Molly Hooper in Sherlock

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During a panel discussion at the Radio Times Festival over the weekend, the 36-year-old actress was asked whether she preferred locking lips with the star or smacking him. "Well, kissing - but slapping was great because I did an accidental theatrical one because I'm an idiot," she explained. Louise said she was "getting excited" while filming but was told by the crew that they could "see her hand" not making contact with Benedict.

Molly repeatedly hit Sherlock across the face after he came out of hiding in series three of the drama. In the scene the super sleuth winced as he replied: "Sorry your engagement's over. I'm fairly grateful for the lack of ring." The mortician previously smooched with the famous detective in an unforgettable dream-esque sequence that saw him bungee jump off the side of St Bart's Hospital in London before breaking through a window and passionately kissing Molly.

Louise went on to describe 39-year-old Benedict's reaction to her slapping technique during filming: "He told me: 'just hit me in the face" and I did - on his shot, not on mine." The actress was at the festival with co-stars Amanda Abbington and Una Stubbs, creators Mark Gatiss and Steven Moffat, as well as producer Sue Vertue as part of The Woman of Sherlock panel. Louise described Molly as "the best part of me" and added she wasn't as nice as her onscreen alter ego.

BBC Benedict Cumberbatch and Martin Freeman in the Sherlock Christmas special

BBC Benedict Cumberbatch in the series 2 of Sherlock

Sorry your engagement's over. I'm fairly grateful for the lack of ring Sherlock Holmes

Although she couldn't give any details about the upcoming Sherlock Christmas special - which is set in the Victorian era - Louise said that it was her favourite episode to date but couldn't say why. Producer Sue, 55, added that the Christmas special might have been fun for them, but from a producer's perspective "it was hell" because it was "hard to film Victorian". Co-creator and writer Steven, 53, spoke about whether the role of Arthur Conan Doyle's great hero could be portrayed by a woman.

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