When Detective Kat Donovan matches on a dating app with the fiancé who disappeared years before, she learns that some secrets are best left in the past.

When ex-soldier Maya sees her murdered husband on a secret nanny cam, she uncovers a deadly conspiracy that stretches deep into the past.

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 ...