Dairmahl MacEilan is an explorer; no David Livingston hacking his way through the jungle or Roald Amundsen dragging his sledges across the Antarctic wastes. Dairmahl MacEilan is an explorer in time. But a time explorer whose time machine has just been destroyed.
Imagine an alley, narrow, high constantly in shadow, no windows in the walls. The buildings on either side of this alley are five miles high. And at the bottom, instead of a narrow road is a fetid swamp containing a variety of unfriendly creatures. Between the buildings are girders either holding the walls together or keeping them apart, or both.
Dairmahl MacEilan is stuck on one of these girders. Several hundred feet below is the swamp. Several miles above a cold wind blows clouds of snow and ice across the roofs of the buildings. The walls stretch to right and left as far as Dairmahl MacEilan can see. There are more girders a hundred meters away on either side.
This is just one of the messes that Dairmahl MacEilan gets into.