Disguised as one of the members of the Dalek alliance, the Doctor discovers that the Daleks have built a deadly weapon known as the Time Destructor.

Goth has been exposed as the assassin but the game is not over. The Master makes his final bid to release the devastating power of the Time Lords.

Halley Feiffer is an American actress and playwright.

Feiffer graduated from Wesleyan University in 2007. She is the daughter of famed satirist and cartoonist Jules Feiffer, and writer, actor, and comedienne Jenny Allen.

Feiffer's work as a playwright has been produced off-Broadway at the Cherry Lane Theatre and at the Edinburgh Festival Fringe. She won the National Young Playwrights' Contest in 2002.

She has performed off-Broadway in subUrbia, Election Day, None of the Above, Still Life, Some Americans Abroad, and Tiger Be Still.

In April 2011, she made her Broadway debut in The House of Blue Leaves starring Ben Stiller, Edie Falco and Jennifer Jason Leigh, directed by David Cromer.

Her films include You Can Count on Me, Stephanie Daley, Noah Baumbach's The Squid and the Whale and Margot at the Wedding, The Messenger, Jared Hess's Gentlemen Broncos, Twelve Thirty,^[5] and Todd Haynes' HBO miniseries Mildred Pierce.

She also guest-starred on the HBO show Flight of the Conchords in the Season Two episode "Wingmen", and has guest-starred on Ugly Betty, The Good Wife, Law & Order and Torchwood.

_{Biography from the Wikipedia article, licensed under CC-BY-SA}  

American Actor who appeared in Torchwood

Adrienne Burgess  is a British actress, mainly seen on television.

Her credits include: Doctor Who (in the serial The Sun Makers), Blake's 7, Terry and June, Just Good Friends Dickens of London and The Bill.

Bernard Horsfall is a British actor.

He had several roles in Doctor Who. His first part was as Lemuel Gulliver in The Mind Robber (1968). His other appearances were as a Time Lord inThe War Games (1969), Taron in Planet of the Daleks (1973) and Chancellor Goth in The Deadly Assassin (1976). All four of these serials were directed by David Maloney.

Horsfall was born in Bishop's Stortford, Hertfordshire. He has appeared in many television and film roles including: Guns at Batasi (1964), On Her Majesty's Secret Service (1969), Enemy at the Door (ITV, 1978-1980), Gandhi (1982), The Jewel in the Crown (ITV, 1984), The Hound of the Baskervilles (ITV, 1988) and Braveheart (1995). 

Horsfall also appeared, with a faked Swedish accent, as "Christianson" in an episode of "The Persuaders!" entitled "The Morning After" during 1972.

In 2003 he appeared in Davros - a Doctor Who audio drama produced by Big Finish Productions.

Biography from the Wikipedia article, licensed under CC-BY-SA

Jonathan Moore was a producer and later Head of Light Entertainment at the BBC, before leaving in 1999.

Obituaries: Guardian, Independent

John Lucarotti was a British screenwriter.

Lucarotti began his career at the Canadian Broadcasting Corporation, writing on over 200 various scripts.  

In the UK he created the television series Operation Patch, which he then novelised, The Ravelled Thread and The Panther's Leap. He wrote ten episodes for The Avengers, thirty-two episodes for The Troubleshooters and contributed several episodes to Doctor Who in the 1960s. 

He subsequently novelised his scripts for Target Books. He also contributed a script for what ultimately became the 1975 serial The Ark In Space, but it was rewritten by script editor Robert Holmes, and Lucarotti received no on-screen credit. He also contributed to, among others, Star Maidens, The Onedin Line, Lieutenant Hornblower, Into The Labyrinth, Kippers and White Wine, United!, Moonbase 3 and Joe 90.

John Lucarotti also wrote for French and Swiss television. He died in Paris.

Peter Welch  was a British actor who appeared in various television programmes including Dixon of Dock Green, Z-Cars, Spy Trap, Softly, Softly, Doctor Who, and Danger Man with Patrick McGoohan.

He appeared in the 1976 story The Android Invasion.