We’ve had much communication over the past few days over what is occurring with filming on the second series of Sherlock. Now, we don’t have an inside line, but with a healthy spot of deduction and a dash of our own speculation, we’ve pieced together the following guide of what has occurred thus far on the production. The episodes are presented in the order they are being filmed, with the code at the beginning denoting their broadcast order.

Broadcast itself is expected in the UK in early 2012, with The United States in May 2012. Other territories are currently unknown.

S2E2 - The Hounds of Baskerville
Filming commenced Monday 16 May 2011. Completed Friday 10 June 2011, after 22 days filming.

No filming in London seems to have occurred for this episode, taking place in small villages, a former gas works, the countryside around Cardiff, and apparently on Dartmoor. The last two days were spent on the 221B interior set at the BBC studios in Cardiff.

The episode moved to editing on Monday 13 June, and post production will continue as S2E3 films.

Main Cast:
Benedict Cumberbatch - Sherlock Holmes
Martin Freeman - Dr. John Watson

Guest Cast:
Russell Tovey - Henry Knight
Sasha Behar - Dr Louise Mortimer
Simon Paisley Day - Barrymore
Rosalind Knight - Grace
Stephen Wright - Fletcher
Will Sharpe - Lyons
Gordon Kennedy - unknown

Crew:
Paul McGuigan - Director
Mark Gatiss - Writer


S2E3 - The Reichenbach Fall
Filming commenced Monday 20 June 2011 on the 221B interior set at the BBC Studios in Cardiff, followed by several days at historic sites including Newport Cemetery, Cardiff Castle, Tredegar House, and Cardiff City Hall, as well as other areas around Cardiff including Broadway and Cardiff Bay.

Production moved to London, taking in the redressed North Gower Street for Baker Street exteriors, as well as other locations around the city including two days at Smithfield Market.

Principal photography completed on the evening of Sunday July 17 2011 after another 22 days filming. The crew returned to London for a day of additional photography for the episode on Wednesday 24 August 2011, which also saw the final day of filming on the series.

Post production will proceed as S2E1 films.

Main Cast:
Benedict Cumberbatch - Sherlock Holmes
Martin Freeman - Dr. John Watson

Recurring Cast:
Mark Gatiss - Mycroft Holmes
Andrew Scott - Jim Moriarty
Rupert Graves - D.I. Lestrade
Vinette Robinson - Sgt Sally Donovan
Louise Brealey - Molly Hooper
Una Stubbs - Mrs. Hudson
Zoe Telford - Sarah
Jonathan Aris - Anderson

Guest Cast:
Peter Basham - Reporter
Robert Benfield - Auction House Director
Jaye Griffiths - Prosecuting Barrister
Ian Hallard - Mr Crayhill [Defence Barrister]
Samantha Holly Bennett - Sky Reporter
Edward Holtom - Max Bruhl
Christopher Hunter - Prison Governor
James Lawrence - School Teacher
Paul Leonard - Bank Director
Pano Masti - Dark Man
Tanya Moodie - Ella
Michael Mueller - Father
Katherine Parkinson - Kitty Reilly
Malcolm Rennie - Judge
Tony Way - Unknown

Crew:
Toby Haynes - Director
Stephen Thompson- Writer

S2E1 - A Scandal in Belgravia
Filming commenced on Monday 25 July on the 221B set at the BBC Studios in Cardiff.  On Tuesday 2 August a day was spent at Bristol South Pool filming the resolution of the series one cliffhanger. Shooting then moved to London on Saturday 6 August for several days, where locations included work at North Gower Street for 221B exteriors and a day inside Battersea Power Station.

After returning to Cardiff and completion on the 221B interiors, the crew returned to London, where filming on the episode concluded in North Gower Street on Tuesday 23 August just after 23:00BST, after a total of 25 days of filming.

Post production may occur from mid to late August into September.

Main Cast:
Benedict Cumberbatch - Sherlock Holmes
Martin Freeman - Dr. John Watson

Recurring Cast:
Mark Gatiss - Mycroft Holmes
Andrew Scott - Jim Moriarty
Rupert Graves - D.I. Lestrade
Vinette Robinson - Sgt Sally Donovan
Louise Brealey - Molly Hooper
Una Stubbs - Mrs. Hudson

Guest Cast:
Warren Bertram - Mr Chaterjee
Richard Cunningham - Mr Wickes
Nathan Harmer - Phil
Andrew Havill - *Spoiler*
Nigel Ipinson-Fleming - Policeman
Darrell Las Quevas - Plummer
Lara Pulver - Irene Adler
Thomasin Rand - ‘Beautiful Woman’
Rosemary Smith - ‘Large Woman’

Crew:
Paul McGuigan - Director
Steven Moffat - Writer