Donna Noble's Wedding

Donna Noble is about to become married to the man she loves, Lance Bennett – but as she walks down the aisle she's enveloped by glowing energy and whisked away leaving a stunned congregation of family and friends in the church.

Meanwhile, in his TARDIS, The Doctor is equally stunned at Donna’s appearance in his time machine. After an initial argument, Donna finally begins to realise that The Doctor is not responsible for her abrupt departure from her own wedding but is equally oblivious as to what has happened.

The Doctor attempts to take Donna back to Earth in time for her wedding. But when their taxi driver realises they have no money to pay the find themselves back on the pavement. It is when The Doctor goes off to obtain some money from a cash dispenser that he spots the same Santa Claus band, who turned out to be 'pilot fish' robots, he saw the previous Christmas and realises something very strange is going on.

Being Whisked Away

Donna meanwhile has managed to borrow some money and enters another taxi... which unbeknown to her has been commandeered by one of the 'pilot fish' robots still in his Santa disguise. The Doctor is too late to stop Donna and so, back in his TARDIS, he makes a daring rescue, hovering over the motorway he gets her to make a leap of faith from the speeding taxi into the TARDIS. And so he finally manages to take Donna to the wedding reception which it seems is taking place without her.

However, it is not long before The Doctor realises that the 'pilot fish' robots have caught up with Donna again and after almost killing everyone at the party The Doctor, Donna and Lance manage to escape. It is then that The Doctor realises that Donna has somehow been infected with Huon energy - an ancient type of energy particle.

A Startled Donna

The Doctor, decides to visit the company where Donna and Lance work - H C Clements – where, in a subbasement, they find a long corridor that eventually leads to a Torchwood science base beneath the river Thames. There they find someone has been experimenting with Huon energy in liquid form. The Doctor realises that whoever infected Donna has a plan – but it was sidetracked when the energy within her was attracted to the TARDIS.

The Doctor soon discovers that the plan has been orchestrated by the Empress of Racnoss - an ancient spider-like being that has arrived in orbit around the Earth in a giant web ship. When she realises that The Doctor and Donna are inside Torchwood she transports herself into the base. The Empress it seems is the last of her kind except for millions of hatchlings inside an ancient Racnoss ship, bearing , inside the Earth's core – it having reached there when the Earth was created millions of years ago.

The Empress has come here to the Torchwood project after having had a 4000-mile-long cavern drilled underneath the base, reaching to the centre of the Earth. She is about to awaken the Racnoss hatchlings and also unleashes a terrible wave of destruction from her web ship.

The Doctor

Realising he has no choice but to stop the onslaught, The Doctor is forced to use The Empress' own weapons to puncture the walls of the Torchwood base, causing an enormous flood that drains the Thames and which pours into the shaft to the centre of the Earth, destroying the Empress and her now-awakened hatchlings. With the Empress distracted an army tank then destroys the web ship.

With the threat over it is just a matter for The Doctor to return Donna to her family – or will she decide to stay with The Doctor now that Rose Tyler is no longer with him?