Doctor Who star Peter Capaldi has revealed he carried around a scrapbook to help him get the character right in the months leading up to his debut.
The star, who recently completed his first full series as the Doctor, said he compiled quotes and pictures which he snipped out for reference as he tried to build up his part in the BBC One drama series.
And he admitted his more "distant" performance was partly a reaction to the more friendly portrayal of the Time Lord from his predecessor Matt Smith.
Speaking at the launch of Doctor Who series eight on DVD, Capaldi said he needed to gather inspiration to work out how he would play the latest regeneration.
He said: "You know, when someone says to you how would you feel about being the new Doctor Who, you go 'waaaahhh' - it's just like having an enormous injection of madness and it's a dream and it's crazy and wild and then there comes a day where I've actually got to do this, I've actually got to go and be Doctor Who.
"What do I do? How do you prepare for that? I've no idea because the last time I played Doctor Who was when I was nine in the playground.
"So I thought I'd better do something so I just started this book where I collected images and quotes and things - I'd look at the world and see if there were people who I thought were vaguely or very particularly Doctor Who-ish. And put quotes in the book, put pictures in there."
Capaldi said he was gradually able to build his character from his reference points.
He went on: "In a way, looking back at it now, I think you react against the last Doctor, because Matt was so wonderful and so accessible and so friendly and so easy to know, I thought we have to be a little different from that - be a little more distant.
"And also a little more ... I'm a man of a certain age so I have to be appropriate to that age - 2,000 years old."
The new DVD was released this week.