Sherlock's return to the small screen was enjoyed by nearly ten million viewers on New Year's Day, most of whom revelled in the visual invention, witty banter, romantic revelations and intrigue on display in Steven Moffat's contemporary take on an old favourite.
But some viewers were left disturbed by the sight of actress Lara Pulver, playing self-described 'recreational scolder' Irene Adler, completely naked apart from high heels and diamond earrings, tantalising Sherlock Holmes with her svelte form and a gleefully brandished whip - all nearly half an hour before the 9pm watershed.
The Daily Mail reports a bunch of Twitter complaints, including this one: "Dominatrix?! Watershed anyone? My ten-year-old was watching that."
And the Telegraph pointed out that Adler had already been seen wearing a thong, walking towards a woman tied to a bed, again with whip in hand.
A BBC spokesman said: "We're delighted with the critical and audience response to the first episode, which has been extremely positive, and have received no complaints at this stage."
Lara Pulver, the actress behind Irene Adler's mischievous style, has thrown her hat into the mix, telling Sun readers that star Benedict Cumberbatch who plays Holmes told her to "whip him harder".
"I was like, 'Oh can I now, Benedict Cumberbatch?" the actress told the Sun.
"Imagine how many whips I am going to receive in the post now!"