Intended as an introductory scenario - and released as a free download - this is a fast-paced adventure that can be run in a single session designed to give 'screen time' to as many different character concepts as possible, yet give a true flavour of what the universe inhabited by the Doctor is really like. Incidentally, if you have the original Doctor Who: Adventures in Time and Space box set (the one with the Tenth Doctor played by David Tennant on the cover), this is one of the adventures that came with it, also released in one of the scenarios in the Tenth Doctor Adventure Book.
Firstly, a section called What's Going On gives the GM the lowdown on what is really happening, then we're off with a Prologue that assumes the characters have met the Doctor and already seen him in action. It also assumes that Amy Pond is there. If your group are not the Doctor's companions (or potential ones) you'll need to devise something of your own although a few guidelines are given for a UNIT party or even people who as yet have not begun to travel in time and space. Then there are lots of notes about the town of Arrowdown itself, complete with a photo of the Eleventh Doctor capering around on a rocky beach called Macross in South Wales - slightly disconcerting as I can think of at least two or three other seaside towns in South Wales that would fit Arrowdown much better - Porthcawl or Penarth, for example. But I digress...
As the party explores the town they will (hopefully) begin to notice that everything's just a little bit off. Incongruities abound. Their investigations will lead them to discover what's going on and suggest a possible solution. Several possible solutions are given, making it easy for you to run with whatever the party comes up with... or make suggestions, should they prove baffled by the whole situation. This makes for a dynamic, fluid feel to the adventure... and one that's great fun to run (I cannot answer as to what's it's like to play!).