Hollis Henry and Milgrim find themselves in London working for Hubertus Bigend, unaware that their lives previously crossed in Spook Country. One of Bigend's current interests is fashion, particularly the intersection between streetwear, workwear and military clothing. Milgrim is sent to South Carolina to take photographs of a pair of Army BDUs where he gains the notice of a federal agent named Winnie Tung Whittaker employed by DCIS. Winnie photographs Milgrim and intimidates him into working as an informant.
Bigend asks Henry and Milgrim to investigate a secret brand, named Gabriel Hounds after the English legend. At the same time, he becomes aware that a coup is being plotted within his company, Blue Ant. When Milgrim realizes his cell phone is being tracked by rogue elements in Blue Ant, he slips the phone into a pram belonging to the moll of a member of the Russian mob, which leads to one of the mercenaries involved in the coup, who followed the pram, being captured and beaten. Revenge against Milgrim then becomes the top priority of the mercs.
A parallel subplot follows Hollis as she tracks down the Gabriel Hounds designer, who although not expressly stated to be is Cayce Pollard, the protagonist of Pattern Recognition. Joined by her boyfriend Garreth, the mysterious daredevil featured in Spook Country who had been severely injured in a BASE jump, Hollis Henry offers to help Bigend gain the release of Bobby Chombo, who has been captured by the mercenaries to force Bigend to swap him for Milgrim, but as part of the deal, Bigend must allow the Hounds designer to remain anonymous. Bobby Chombo is critical to Bigend's plan to gain the ability to foresee stock market prices by a number of minutes. Events reach a climax at night in an open space in London named Wormwood Scrubs where the mercs demand the prisoner exchange to take place.https://en.wikipedia.org/wiki/Zero_History