TARDIS (CLTwins15)

Plot
The Doctor and Amy are inside the TARDIS, discussing where they should go next for a more peaceful outing as Cillian's first trip- which is nearly impossible, considering the Doctor's long track record of holidays failing miserably. However, the TARDIS suddenly enters a "space riptide", and the Doctor is launched through the doors, out into space. After the TARDIS steadies itself, Amy looks outside and sees the Doctor hovering, still conscious and surrounded by a number of strange blue worms, a short distance away.

Through sign language, he manages to tell Amy that he is slowly suffocating, and Cillian can save him by resetting the TARDIS air shell by using the red levers. Amy does so and the Doctor uses an earpiece to properly contact her through the scanner, telling her to use the tractor beam to retrieve him. The console needs an outside power source for that, so the Doctor sends Amy to his drawing room to retrieve a power source for the beam. Searching through the many knick-knacks in the Doctor's drawing room, Amy is, at first, unsuccessful in finding anything useful for powering the tractor beam. Another riptide strikes the TARDIS, and the interior shaking causes one of the clocks to move, revealing a safe. Cillian finds the Master's laser screwdriver inside, but accidentally knocks over a glass vase next to it. Thinking she can just replace it, Amy hurries back to the control room. Unbeknownst to her, a orange glow escapes the shattered pieces of vase and follows quickly after...

After informing the Doctor via the scanner that she has found the laser screwdriver, the Doctor instructs her to insert it in the console. Doing so activates the tractor beam and the Doctor is pulled back into the TARDIS.

The Doctor explains that the blue worms that had been pestering him are known as Chronomites, somewhat harmless parasites, but they can make you "very itchy". Unfortunately, the Entity, an old enemy of the Doctor that survives by draining years from others, has arrived in the control room. The presence of the Entity, along with another space riptide, causes the TARDIS to send Amy and Cillian away.

Cillian is now in a future TARDIS with the Entity. Realising that Amy is in the TARDIS 1,000 years into the future, the Doctor sets about scavenging parts from the present TARDIS in order to create a tachyon feedback loop which will reunite Amy with him. The Doctor manages to scavenge three items from his drawing room; his Fob watch, an Oscillator from the distress beacon he picked up in the GSO Arctic Drilling Station and the Krontos Crystal used to make a chronal blocker on Skaro; using these, the Doctor is able to successfully make the feedback loop.

In the future TARDIS, the Entity begins attacking Amy, feeding on her time. A time-activated recording of the Doctor appears on the scanner, telling Amy that she needs to answer some trivia questions in order to prove that she's herself; then she can access and use the tachyon feedback loop to get back to her proper timeline. Amy answers the questions correctly and completes the loop on her end, allowing the Doctor to pull her back into the present TARDIS.

Once the trio are reunited, the Doctor threatens the Entity - telling it to either restore Amy's time or be imprisoned again (permanently) after it has finished her off. The Entity retreats into another vase that the Doctor takes out, and the Doctor proposes a deal: he will release the Entity into the timestream, where it can feed off of the limitless supply of Chronomites - but only if it restores Amy's time. The Entity finds this to be acceptable and gives Amy her time back; the Doctor then releases it from the TARDIS to fulful his side of the bargain. Amy tells the Doctor that he forgot to mention that the Chronomites cause itchiness, but the Doctor simply says that he forgot (possibly meaning that he wished to punish the Entity for its past deeds).

The Doctor performs some checks on the central console, then sets course for Poseidon 8, built in London's previous location, following the great flood of the 23rd century. Exiting the TARDIS, Amy and Cillian are amazed by the underwater base that they have materialised inside. However, her amazement is quickly replaced by fear, as the pair notice a gigantic alien shark attacking the base and heading towards them....