LONDON - Only 5.9 million viewers tuned in to watch Benedict Cumberbatch in the series finale of the BBC drama Sherlock on Sunday.
That was the lowest-ever overnight viewership for the hit series since Cumberbatch started playing the detective in 2010.
The figure was down from the 8.1 million who watched the first episode of the series' season four on Jan 1.
The ratings drop came after the Russian version of the episode, titled The Final Problem, leaked online just hours before BBC One's broadcast.
Russia's Channel One was to air that episode simultaneously with Britain. But the dubbed episode was leaked online on Saturday and swiftly copied across numerous sites.
Channel One blamed hackers for the leak while the BBC has said it was launching a full investigation.