'A Study In Pink', a modern-day adaptation of Arthur Conan-Doyle's 'A Study In Scarlet', was seen by an audience of 7.5m and was yesterday revealed to have achieved a high AI rating of 87.
Metro's Keith Watson praised Benedict Cumberbatch and Martin Freeman, who played the 21st century Holmes and Watson.
"I like Benedict Cumberbatch in the title role. He has the right edge and energy, the razor-sharp mind, but also the lack of social skills and impatience that appears to border on cruelty," he said.
"Martin Freeman's Watson is very good, too - closer to Conan Doyle's thoughtful narrator than the bumbling fool so often portrayed on screen. Their relationship is spot on - a mixture of frustration, admiration and genuine affection."
The Guardian's Sam Wollaston was less complimentary, particularly about the show's time period. "In blowing away the fog, brightening it up for the 21st century, they've done away with the fear as well. It's slick, and quick, and yes, compelling. But there's also a sanity about it, a pantomime squeaky-cleanness," he wrote.
However, The Daily Telegraph's Harry Mount argued that the fictional detective's "allure spreads beyond period detail".
He wrote: "So, there was instant comedy in Cumberbatch dismissing the expert opinions of forensic scientists and senior policemen.
"Where other detective shows would need a careful, drawn-out explanation of why our man is right and the others wrong, Holmes carries with him the assumed baggage that he is always right. He can afford to be dismissive and superior, yet we're still on his side."