[Note: This assumes you've seen the first couple weeks of the new series of Doctor Who. I've put the seed after the jump for the benefit of those who haven't.]

Dorabella

Professor Edwin Bracewell was a Dalek creation, but the Doctor and Amy gave him a new lease on life. He’s decided to use the time to look for a long lost love – Dorabella. But just as he manages to locate her, someone else manages to locate him – the Daleks. Not pleased that their invention had betrayed them, they waited until their army was stronger – and came to EXTERMINATE him, and the rest of the Earth around him while they were at it. With the love of his life in tow, Bracewell must put a stop to the Dalek plot without revealing his shameful secret to Dorabella.

Things to Prepare For: The PC playing Bracewell will likely want to tap into some of his Dalek knowledge to help create something to stop them.
Antagonists: The Daleks, of course – primarily the Orange “Scientist” variety, eager to crack open and reuse the android technology. Possibly Bracewell isn’t the only Dalek android around, as well.
Problems: How will Dorabella and the other PCs stop Bracewell from exploding if the Daleks access the Oblivion Continuum again?

On the planet of Thorthasn, the people take energy from radio waves that echo around the atmosphere of the planet. These waves are only broadcast for part of the year though, and they hibernate for the rest. When the Doctor and his companions arrive, they come just when it’s time for the hibernation to end. Eager to show his companions the celebration that occurs, the Doctor quickly sets up a brief camp and sets his scanners to detect the growing power of the waves.

They arrived just in time, and within a few minutes of them setting up camp, the scanners already show the growing power, and it isn’t long before they’re approaching 100% capacity. But just before the counter ticks over, something happens – the power starts to decrease.

The group soon isolates this to another set of waves adding against the natural ones of the planet. But what’s creating the waves? Why do they want to make sure that the Thorthas never wake up? And more importantly, can the Doctor and his companions make sure that they stop the destructive wave before the Thorthas waste away?

Stuff to be done: Create a detector for the radio waves. Trace the destructive wave. Find a way to wake up the Thorthas.
Antagonists: Rukran, a species that left their planet when it was destroyed and settled on Thorthasn when the natives were all hibernating.
Problems: Will the players help the Rukran settle somewhere else? Or just destroy them?

So the TARDIS crash lands. Normal enough – it’s Wednesday. Since it takes the internals of the ship a little while to recalibrate, the Doctor and his companions decide to take a quick jaunt onto the surface of the planet they’ve landed in.

Luckily, they picked a beautiful planet to crash land on. A lush, tropical rainforest covers the land, full of beautiful flora and fauna, some of which even the Doctor doesn’t recognize. Eventually, the Doctor realizes that the TARDIS has had plenty of time to calibrate and decides it’s time for them to head back. Unfortunately, they got so turned around in the forest that they can’t find their way back!

As they start to construct a rudimentary tracking device for the TARDIS, one or two of the less scientifically-minded companions start to wander around close to their temporary base. They come upon a nest of animals, similar to large furry dogs. They’re friendly enough, and the companions have fun playing with them for a few minutes. Unfortunately, the father doesn’t take kindly to this, and he’s a good bit bigger than the babies.

And then, just when they thought things couldn’t get any worse–

Stuff to be done: Explore the jungle they’ve landed in. Find a way to build a tracker for the TARDIS.
Problems: The native people on the planet think the fact that the jungle beast attacked the travelers means they must be put up for sacrifice.
Action Scenes: Fend off the giant jungle creature to protect those finishing the tracker.
Things to prepare for: Interactions with the flora and fauna in the opening scenes.

On the planet of Dydd, one side of the planet always faces the sun, leaving it in constant sunlight. Blessed with the eternal light, Dydd is home to one of the most beautiful sights in their galactic quadrant – the Sun-Touched Gardens of Northern Dydd.

After a couple of weeks without anything interesting happening, the Doctor decides to take his companions to the Gardens to show them some of the beauty of the universe. All is well at first, until, shortly after their arrival, the Doctor notices that the sun has begun to set, and darkness is beginning to take hold for the first time in recorded history.

For two weeks, the planet of Dydd is plunged into panic. The Doctor and his companions must maintain order as the planet begins to spiral out of control – and find out what is behind the sudden darkness.

Stuff to be done: Find a source of light in a world that has never known darkness. Investigate the cause of the planet’s rotation. Calm down everyone on the now-darkened side of Dydd. Figuring out why the Drych turned the planet around – and why for only two weeks.
Antagonists: The Drych, humanoid inhabitants of the other side of Dydd. Tawel, a silent monster from the dark side of Dydd.
Action Scenes: Running through the Gardens escaping the Tawel. Taking care of rioters.
Things to be prepared for: What happens if the players decide to go to the other side of Dydd?

Kronos, the manufacturer of fine intergalactic watches (Knows where you are and changes the time automatically, regardless of time system – guaranteed!) has just announced their intention to relocate their operations to the recently discovered AX-435132, aka the Telos Neubla. Unfortunately, as soon as they flip the switch and turn on their plant, something starts to go horribly wrong.

Enter the Doctor and his companions. Hoping to catch a glimpse of the unusual light patterns visible only in the Telos Nebula, they’re disappointed to find their view blocked by a concrete factory. However, the Doctor begins to take an interest when some of the employees begin to fall ill in time with their clocks! Perhaps relocating to the nebula wasn’t such a good idea.

Stuff to be done: Convince the CFO of Kronos that the Telos Nebula isn’t safe. Find the connection between the light patterns and the countdown. Figure out how to cure those who are already affected by the countdown.
Problems: One of the player character’s watches start counting down as well – better hurry up!
Action Scenes: Escape guards who think they’re intruders.
Things that need preparing for: What happens when you remove the watch of someone afflicted?