The Eternity Trap

16 – The Eternity Trap
The Sarah Jane Adventures story
Cast
Starring Elisabeth Sladen – Sarah Jane Smith Daniel Anthony – Clyde Langer Anjli Mohindra – Rani Chandra
Others Floella Benjamin – Professor Rivers Donald Sumpter – Erasmus Darkening Callum Blue – Lord Marchwood Adam Gillen – Toby Silverman Amelia Clarkson – Elizabeth Marchwood Rhys Gear – Joseph Marchwood Tony Boncza – Mr Scriven
Production
Writer	Phil Ford
Director	Alice Troughton
Script editor	Gary Russell
Producer	Nikki Wilson Phil Ford (co-producer)
Executive producer(s)	Russell T Davies Julie Gardner Piers Wenger
Production code	3.7 and 3.8
Series	Series 3
Length	2 episodes, 25 minutes each
Originally broadcast	5 & 6 November 2009
Chronology
← Preceded by Followed by → The Wedding of Sarah Jane Smith Mona Lisa's Revenge

The Eternity Trap is a two-part story of The Sarah Jane Adventures which was first broadcast on CBBC on 5 and 6 November 2009. It is the fourth serial of the third series. The story involves the scientific investigation of a haunted castle.

Plot

Part 1

Professor Rivers tells the story of Ashen Hill Manor, which is said to be haunted. She talks of a man named Lord Marchwood and how he employed Erasmus Darkening. Lord Marchwood thought that Erasmus could make gold out of base metals. His two children, Elizabeth and Joseph, spy on Erasmus. He spots them and makes them vanish. Rivers is telling the story to Sarah Jane, Clyde and Rani. She and her assistant Toby are making a scientific investigation of the ghostly phenomena. Luke is at home as he has no interest in ghost-hunting. Sarah Jane splits up from the group and finds a book on the history of the manor. She turns round from the book case which she is reading from and unknown to her, the books begin moving. Clyde and Rani go outside and find a dry fountain. All of a sudden the fountain starts and some wet foot prints appear leading in the direction of a shed. Clyde and Rani hear a young girl crying, and enter the shed. The crying stops as Clyde pulls a sheet off a mirror. A strange man's face appears in the mirror. Clyde and Rani run back into the manor and find Sarah Jane. Meanwhile in the control room the camera in the playroom cuts out. Rivers goes to investigate. The baby monitor starts to play, then seconds later the professor vanishes. They all go to investigate and they find that all the toys have started to move on their own. On the mirror in the room a message appears saying "GET OUT". Clyde and Rani begin exploring and find a secret passageway; they go down and find Erasmus' lab. Meanwhile Sarah Jane goes out onto a balcony. A creature in the bushes with red eyes appears and advances towards Sarah Jane. But Lord Marchwood's ghost manifests and fights off the creature. Clyde and Rani find a computer, then when they turn around they see Erasmus Darkening.

Part 2

Lord Marchwood arrives to rescue Clyde and Rani. Then they are aided by his children. Sarah Jane hears a recording of Professor Rivers saying "Sarah Jane help me" over and over. Then she sees her. She warns her that "he is coming for you" and then disappears. Sarah Jane reunites with Clyde and Rani and then they find Lord Marchwood. Sarah Jane believes they're not ghosts. Toby, Sarah Jane, Clyde and Rani discover all the people that have disappeared except for Professor Rivers who hasn't been absorbed yet. Erasmus arrives and they all disappear. Erasmus tells them he will come for them all. Sarah Jane knows Erasmus is playing with them. Sarah Jane and Toby investigate Erasmus's secret chamber while Rani and Clyde distract Erasmus. Toby tells Sarah Jane about a creature who came into his room and watched him every night when he was younger. Rani and Clyde are chased by something into a game room. When all the games start playing themselves they run outside and get locked out. Sarah Jane and Toby find Erasmus's machine. Sarah Jane suspects that Erasmus was trying to get home to another galaxy with the machine. The machine malfunctioned and all the people that disappeared got trapped between dimensions. Clyde and Rani run into the pavilion. Sarah Jane and Toby get interrupted by Erasmus. Sarah Jane works out that the machine is giving Erasmus and all the people that disappeared immortality. She also works out the creature that attacked her earlier came through the machine. Lord Marchwood once again rescues Clyde and Rani again by slaying the creature. Sarah Jane, Clyde, Rani and Toby reunite along with Lord Marchwood. Sarah Jane comes up with a plan to stop Erasmus. They can turn him into electricity but he has to step into a certain area. Lord Marchwood uses his sword and a wire to connect to it to do it. Erasmus is destroyed and Professor Rivers is returned. Sarah Jane destroys Erasmus's machine with the sonic lipstick. Sarah Jane, Clyde and Rani say goodbye to Professor Rivers and Toby. Sarah Jane says that she still doesn't believe in ghosts. They drive away. We then see Lord Marchwood and his children at the window.

Continuity

• Tommy Knight was not available for filming of this episode due to his GCSE exams. This story is therefore the first not to feature Luke Smith. As a result of this absence, Elisabeth Sladen becomes the only cast member to have appeared in every episode of the series. Other series mainstays such as Mr. Smith, the Smiths' attic and Rani's parents do not appear in this story.
• Professor Celeste Rivers and the Pharos Institute were previously shown in The Lost Boy and The Day of the Clown.
• This is the first episode with scenes set prior to Sarah Jane's birth.

Outside references

• The "Stone Tape Theory" mentioned in this episode is a reference to The Stone Tape by Nigel Kneale and it's also mention in the Doctor Who Past Doctor Adventure The Eleventh Tiger.
• In Erasmus' lab, Clyde comments: "This is Hogwarts Tim Burton style! It's... Harry Potter has a close shave off Sweeney Todd." Later (when being cornered by Erasmus), Rani remarks: "This is worse than The Sixth Sense."
• Clyde wisecracks, "I ain't afraid of no ghost," a reference to the Ghostbusters franchise. Later, trying to attract Darkening's attention, he says "We've come to bust you," and Rani adds, "I'd feel a whole lot better if I was wearing a Ghostbusters Proton Pack right now."

External links

• The Eternity Trap on TARDIS Data Core, an external wiki
• The Eternity Trap at the Doctor Who Reference Guide
• The Eternity Trap at Doctor Who: A Brief History of Time (Travel)
• "The Eternity Trap" at IMDb