The ‘Derailleur Code’ is a classic tale of good versus bad (writing).
Cycling historian Professor Claude B Dawes finds himself hired by Dr Moeller (of the M7 Human and Alternative Powered Vehicle Company) on a mission to hunt down Der Bromptonaut, an agent of the mysterious ‘Brotherhood’. This shady organisation is sworn to the elimination of all bikes that don’t fold and anyone that stands in their way. Dawes now believes that his evil opponent has been able to make a copy of the top secret M7 AM10 36 spoke hub - a bike part so powerful that it has to be kept moving to avoid going ‘critical’.

In the previous chapter the ‘code’ simply proves to be co-ordinates to a large out-of-town retail park near Varberg, Sweden. As the party pursuing Der Bromptonaut head north on the Swiss Bike Patrol’s specially chartered train, things take a turn for the worse. Professor Dawes enjoyment of a Schubert piano sonata (played on the train’s very own Bösendorfer piano) is interrupted by an ‘outage’ that has brought western Sweden to a halt.

Dawes and Lucyna have now taken to the rails with the M7 state of the art tandem velomobile (equipped with 'wire guided' steering locked by GPS to the perfectly laid track work of Swedish railways). Their aim... to get to Varberg in record time, avoiding traffic jams and big hills. Meanwhile back on the train Moeller, Wallender and the Bike Patrol consider their options. ‘Continuity Control Expert’ Herr Braun watches and notes that the last chapter finished more oddly than usual.