London police officer DC Hana Li is escorting Dr Matthew Nolan back to Beijing where he has been accused of a crime. However, on board flight 357, she finds herself embroiled in an escalating conspiracy and a growing number of murders.

A pair of small-time crooks, Wayne Todd and Fraser Hood, who met in jail are reunited when Wayne leaves London after being threatened by a thug and travels to Glasgow to look up his old cell mate.