He may have a disembodied head in his fridge and eyeballs in his microwave, but what really impressed us with Benedict Cumberbatch's Sherlock was the contents of his wardrobe. We've already told you where costume designer Sarah Arthur got his distinctive coat from - now we reveals further details of all the other costumes from the show and more on the clothing of everyone's favourite consulting detective.

GQ: Have you been surprised by the reaction to Sherlock's wardrobe?

Sarah Arthur: I gather from lots of people who have texted me that it's been very, very popular. People seem to have liked the look of the costumes, which is really good obviously!

Read more: Style File: Benedict Cumberbatch

Was it a fun project to work on?

It was hard! The weather conditions were extremely difficult in January. Fittings were difficult to do because people were snowed in. The actors were very cold, but what was lovely was that they were all delightful to work with. Benedict, Martin, Rupert, Una - they were all lovely. That makes life much easier.

Did Benedict have any say in what his character would wear?

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I always want actors to have an input. There's no point me taking somebody and saying "Just put that on". He's quite lithe, Benedict - the clothes needed to suit him, be appropriate to the character and he needed to be comfortable. I found these Spencer Hart suits which were classic, beautifully cut, the cloth was fabulous and when he put it on he thought it was perfect. It was actually the first thing he tried on! They really did work well - the producers and director were thrilled. Benedict loved his clothes but a lot of his suits were wrecked because he insisted on doing his own stunts. Because the suit cloth was so fine, they took a bashing. We had to buy three complete suits which was very expensive, as well as a separate jacket.

Were all the shirts Dolce & Gabbana?

I did have a couple of Spencer Hart shirts, but they were mostly from the mainline Dolce collection. Again, Benedict is very slim - we needed that silhouette, so that if he was sitting in the flat, I didn't want loads of fabric bulging out. Those Dolce shirts just suited his body - I didn't want anything too unusual or flamboyant.

They were classic with a little lilac pinstripe. Some of the Spencer Hart shirts had a round collar so I tried it on Benedict but it was pushing the point, so I put that on Moriarty, because it was slightly period.

Where was Moriarty's suit from?

His suit was Vivienne Westwood. Westwood can be very extreme but this wasn't. Originally I think in the script it was another make, but the suit was just perfect for him and the colour was different and unusual. I teamed it with a Spencer Hart round collar shirt and an Alexander McQueen tie with skulls on it. It just worked - because it had a slightly sinister feel.

Where did you get Sherlock's shoes?

The original pair were Yves Saint Laurent - they took a bit of a hit running the streets of London! Because when you have narrow trousers and he's got quite big feet, you have to be careful. I had them soled with a thicker sole and because Benedict is quite tall and Martin's shorter, we went for a very small heel for Sherlock. We wanted a longish line but we didn't want pointed toes. I doubled the YSL shoes with Poste which were a damn sight cheaper. They were great and very similar. I picked up a third pair from TK Maxx. They all looked essentially the same. We filmed in this underground carpark which was full of water and I was just cringing about his shoes.

What did you think of Guy Ritchie's Sherlock Holmes?

Excellent - I liked it. You've got your typical period costumes -

I think Jenny Beavan did them really well. They handled hats well because hats are unpopular with cameramen of course because they cast shadows. Obviously with our version it was very much ultra-modern, given all the technology in the story lines.

Where did you actually find the much talked-about coat?

The coat was actually a couple of years old. What happened is that another chap did the pilot and he found that coat. When I took the project on, I inherited all those original costumes from the pilot.

It was the only thing I kept. It was such a lovely coat - a classic. We had three of them because we obviously do stunts and need doubles. It is a lovely coat - really perfect for Benedict. He loved it, I loved it and everyone else seemed to.

Where did Watson's coat come from?

The black jacket is from Haversack. I got a lot of clothes for both Benedict and Martin from Liberty. Liberty had some great stuff - I was very impressed. Whoever their buyer is, they're just perfect. I wasn't overly keen on Watson's original coat from the pilot - but [the character] had just come out of the army so I knew where they were coming from. I wanted to keep him old school, with check shirts, but make it a little bit more interesting. Some of the knitwear I used was modern stuff, not old fashioned. I didn't want it to ever start looking like a fashion show - they were supposed to be able to wear these clothes to accentuate their character.

**Martin Freeman wears that cable-knit jumper very well.

Where did you get it from?**

I knew you were going ask that! It was from a little modern up-to-date shop off Carnaby Street - I cannot remember the name. It was another little find - it had that homely, slightly army-ish feel. Initially with Martin, we went to a big high street department store. I'd never met him before and didn't realise that Martin himself was very stylish - very subtle, but he wears clothes so well. As soon as he walked in the door, I knew we were in the wrong place. He needed to be old school, so he had classic Loake boots. Martin was marvellous - he said "Uniqlo jeans really suit me". When you have the trust of the actor, they'll help you to find the best possible look.

Where did Sherlock's dressing gown come from?

From Harrods. Believe me, budget was very tight and the one I wanted was thousands but I couldn't afford it. I had to find a similar alternative - there is always compromise on these productions. Very pleased with it, but if money had been no object, I had my eye on a lovely cashmere striped one. But when you've got budgets to stick by, you have to control yourself a bit.

Where did Sherlock's scarf come from?

It was an old Paul Smith. Quite a fine knit - Benedict put it on so naturally and it worked every time. It was interesting because there were so many action scenes I needed double of everything, but the one thing I didn't have a double of was that scarf. I was terrified that something would happen and we'd lose it! Things in the business can be so chaotic - particularly when it gets dark early and people drop things from trailers! That scarf was the bane of my life! If I did another series, I wouldn't use that scarf again - I'd definitely do something new!

Given how big tweed is this year, were you ever tempted?

Not really - the only one I would have possibly put tweed on was Martin, but that seemed almost too obvious. We did have a tweed jacket but we didn't go there - we stuck with what we were doing.

Where did you find Sherlock's gloves?

They were from Paul Smith, two-tone black and grey. Benedict said to me one day "Something is happening to my gloves Sarah, they've gone a funny colour!" I said they were always like that! They took a hammering too.

We had a few comments from Twitter about the expense of Sherlock's wardrobe. Are there more affordable options?

There always are affordable ways! I did the first series of Footballers Wives when no one knew what it was. Everything had to be put together - we had to do high fashion on peanuts. What I do is mix and match. I go to TK Maxx where you can pick up very high quality, interesting menswear. It's not designer. There will have been in the costumes bits and pieces that came from the high street. Unfortunately Martin's jacket will be expensive because of the detailing. But you will find similar things. And I have no doubt that you will find a coat similar to Benedict's.

It will be copied - somewhere like Zara will definitely have picked it up. It's all very military now, so there's bound to be something similar.

Which other TV characters dress particularly well?

God, now you're asking! Matt Smith - I like the tweed and bow ties. But I can't say I've seen anything of late that I've thought was that fantastic.

What are you working on next?

I have just done Toast, a project with Helena Bonham Carter and Ken Stott, from the Nigel Slater book - it was great fun, but that was period. I did a lot of designs for that and made suits for him (because he had to get fat) and dresses for her. That is coming out in December. Very hard work, but they're lovely jobs to do when people are nice.

What are your hopes for the second series of Sherlock?

I am not sure whether I am doing it at the moment. One, I have not been asked yet, and two, I do have plans for later in the year. I can't really answer that as it would be a bit presumptuous of me - they may not want me back! I thoroughly enjoyed it. The only thing with a second series is that because they're obviously very happy with their style, it halves the work! It's lovely to do the first series of anything because you can put your own stamp on it, but whoever does the second series would continue along the established lines, because everyone seemed to have liked it. I don't know what you would do - Martin could have a new jacket maybe!

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The Sherlock series 4 release date is 1 January 2017