Benedict Cumberbatch has said that the third season of the hit BBC crime drama series "Sherlock" gives fans a greater look of the detective's personal life, including who his parents are and where he came from.

"You find out about Sherlock's background," the 38-year-old British actor told NPR. "You find out that he comes from a truly stable home. It was a gesture in the first episode ("The Empty Hearse"), but you see that in practice in the third ("His Last Vow"). You see that, as a boy he was deeply insecure - it begins as a taunt [from his older brother, Mycroft (Mark Gatiss)] ... and that comes back to haunt him and he feels like a child. He's reduced to feeling like a child."

Cumberbatch revealed that he thinks those storylines came from the conversations he had with series' co-creator and producer Steven Moffat early in production of the show's first season.

"Immediately as an actor I wanted to understand who [Sherlock] was, what his parents were," the "Imitation Game" star added. "These were questions I asked ... I wanted to understand."

"[Moffat] was just talking about, 'Can't this guy just be good at what he does and he's your age and he looks like you and he's doing his thing?' And I went, 'No, no Steven, there's a process I've got to go through. I've got to understand how I became this person,'" he recalled.

Cumberbatch also revealed that Moffat initially refused to give Sherlock a flaw.

"[Moffat] said, 'But can't he just be really good? Can't he just be good at it? Why does he have to have flaw or an Achilles heel?'" the "The Hobbit: The Battle of the Five Armies" actor said.

But Cumberbatch insisted that Sherlock should have a weak spot. "I said, you know, 'Where's his weakness?' Because no human being doesn't [have one]. And however much [Sherlock] tries to convince himself he's not human, he is."

And that weakness was shown on last season's third episode, in which Sherlock shot Charles Augustus Magnussen (Lars Mikkelsen) to stop him from blackmailing Mary Watson (Amanda Abbington).

"What he's resorting to at the end is violence," Cumberbatch said. "It's the weakest, weakest thing to do. So, to me, I think that exposes more about Sherlock ... I think you get under the skin of every character with this last season ... This is a really Freudian drama."

Cumberbatch's Nov. 4 interview with NPR coincides with the release of Sherlock Limited Edition Gift Set, which includes all three seasons of the show on DVD and Blu-ray, plus outtakes, new commentaries and collectible resin mini-busts, depicting the show's two leading men, Cumberbatch and Martin Freeman (John Watson), according to The Hollywood Reporter.

In September, Cumberbatch told Empire magazine via BBC America that the upcoming Christmas Special and the three-episode Season 4 of the show are going to be "phenomenal."