Episode 1 (#9.01 - Aired on September 20, 2010)
Directed by Paul Whittington
Written by Jonathan Brackley, Sam Vincent
Additional Episode Cast George Georgiou, Peter Bankole, Jon Ivay, Patrick Regis, Souleiman Ismael, Sandeep Garcha, David Hounslow, Rashmika Torchia
Synopsis Reeling after the explosion at the hotel, Section D are left considering the sacrifices they make as spies. But they are soon back in action, tracking Somalian AQ terrorist Abib on a boat from Tangier. When it becomes clear that the boat is carrying a lethal load, the team fear it is headed to Plymouth for the launch of the newest addition to the Royal Navy's fleet. But is the real target elsewhere, and is it too late to find the UK source of the plan? Lucas's own faith is challenged when he is visited by an unwelcome ghost from his past.

Episode 2 (#9.02 - Aired on September 27, 2010)
Directed by Michael Caton-Jones
Written by David Farr
Additional Episode Cast James Faulkner, Nigel Lindsay, Paul Herzberg, Tom McKay, Victor Zaragoza, Daniel Adegboyega, Steve Toussaint, Joanne Howarth, Katy Barker, Jack Sandle, Richard Jacobs
Synopsis The pressure is on for Beth when she goes undercover for MI5 for the first time. She is tasked with protecting a influential oil baron, Robert Westhouse, when the Team receive intel that an assassination attempt will be made on him at a meeting of top oil dealers. But an unexpected ambush throws things off course, and threatens to dredge up her murky mercenary past. Meanwhile, Lucas visits someone who never expected they would see him again.

Episode 3 (#9.03 - Aired on October 4, 2010)
Directed by Michael Caton-Jones
Written by Richard McBrien
Additional Episode Cast Julian Lewis Jones, Jonathan Aris, Donald Sumpter, Amanda Hale, Nick Sidi, Tom Marshall, Kirsty Wark
Synopsis Section D are forced to welcome an FSB Officer onto the Grid to help track down Aibek, a rogue nationalist from the ex-Soviet state of Azakstan. Aibek is in the UK to find the last known sample of the nerve agent 'Paroxocybin'. The chase is on, but will the team find a way to stop the nerve agent falling into the wrong hands without ruining Anglo-Russian relations? Meanwhile, Lucas's personal life takes a passionate turn.

Episode 4 (#9.04 - Aired on October 11, 2010)
Directed by Paul Whittington
Written by Jonathan Brackley, Sam Vincent
Additional Episode Cast Benedict Wong, Colin Salmon, Daphne Cheung, David Ka-Shing Tse, David Lee, Christopher Goh, Nicholas Lue-Fong, Nigel Whitmey, Matt Selby, Ed Cooper Clarke, Wai Wong
Synopsis When a highly skilled trio of Chinese agents arrive in London for 48 hours only, the team must find out why they are here. Ruth goes undercover in a major scientific research corporation where one Chinese scientist, Jiang, proves to be the ultimate prize. Beth activates an asset from the Chinese Security Services to be Section D's mole on the inside, but has she activated him too soon? Lucas makes a decision that could change his course forever.

Episode 5 (#9.05 - Aired on October 18, 2010)
Directed by Julian Holmes
Written by Jonathan Brackley, Sam Vincent, Oliver Brown
Additional Episode Cast Mounir Margoum, Akin Gazi, Paul Freeman, Maya Lubinsky, Joseph Long, Georgina Rich, Rob Heanley
Synopsis The American president is on his way to London to chair top secret peace talks between Israel and Palestine, under the guise of his first state visit. Beth and Dimitri must keep their wits about them as undercover Home Office representatives, tasked with keeping the delegates apart until the talks. When a plot to kill the President is uncovered, they must also track down the assailant. The hotel is put in lockdown as a precaution, but are they locking the threat out? Or in?

Episode 6 (#9.06 - Aired on October 25, 2010)
Directed by Julian Holmes
Written by Jonathan Brackley, Sam Vincent
Additional Episode Cast Fiona Glascott, Colin Salmon, Hugh Simon, Alec Utgoff, Uriel Emil
Synopsis Relations between the CIA and MI5 are stretched after an American drone is hacked in Afghanistan whilst in British care, leading to the loss of American lives. Beecher - head of the CIA in London - arrives on the Grid to oversee installation of the US's advanced cybersecurity system, 'Cybershell', to prevent any future disasters. Lucas, out in the field, is tasked with protecting and delivering to the Grid Daniella Ortiz, the young ex-hacker turned White House cryptographer who holds the installation codes. When the Grid is hacked and locked down, the Team are plunged into a nightmare. Will they escape and prevent the theft of all CIA and MI5 intelligence? Will Lucas be able to protect Ortiz when the hackers decide to cut out the middle man?

Episode 7 (#9.07 - Aired on November 1, 2010)
Directed by Edward Hall
Written by Anthony Neilson
Additional Episode Cast Hugh Simon, Trevor Cooper, Hi Ching, James Daffern, Robert Hitchmough, Dave Legeno, Rosalie Craig
Synopsis Lucas is plunged further into the depths of his past when Vaughn takes his manipulations to a new level. Ruth is approached and followed by an imbalanced council snooper who is convinced he's found a dead drop. She initially keeps her distance from him, but when her curiosity gets the better of her she ends up trapped in a situation not even he could have predicted. Lucas and Harry come face to face in the pursuit of the truth.

Episode 8 (#9.08 - Aired on November 8, 2010)
Directed by Edward Hall
Written by Jonathan Brackley, Sam Vincent, Richard McBrien
Additional Episode Cast Vincent Regan, Hi Ching
Synopsis The team face their toughest challenge ever: tracking down Lucas North, their Section Chief, friend and one of the best agents MI5 has ever had. Harry decides the team are too close, and brings in a specialist to help with the hunt. But it will not be easy to find a man who has nothing left to lose, and as the search becomes increasingly desperate, Harry and Lucas become embroiled in a deadly game of cat and mouse.

Sophia Myles plays Beth Bailey who comes from a background in private security and joins the MI-5, Section D Team as Junior Case Officer. The character is based on a real-life person's life. Due to unknown reasons Beth Bailey wasn't brought back for series 10. Her character was demoted off-screen. Erin, who got Harry's job said in episode 1 of series 10: Her conduct during the West House operation, her links with the Columbian drug cartel were unacceptable. I expect higher standards.

• Filming Locations: London, England

• The series airs with no credits on BBC One, to maintain an atmosphere of the anonymity of real-life spies and the drama of each episode.
•  The character of Beth Bailey is based upon a real life English spy whom Sophia has met up with.

Daily Mirror

Sophia Myles is already proving to be a most exciting addition to the Spooks team.