|The Algebra of Ice|
'The Algebra of Ice', written by Lloyd Rose, features the Seventh Doctor and Ace.
Back Cover Blurb
A genius maths nerd, a weird webzine publisher, and the Doctor's old ally, the Brigadier find themselves helpin the Doctor and Ace solve what should be a simple puzzle: the appearance of a crop circle in the Kentish countryside.
Hardly uncommon. Buth there are some peculiar features. It's not a circle bu a series of square sided shapes. It's filled with ice. And it draws the Doctor and Ace into a confrontation with a reality right next to zero.