Over their dinner together, Ruth and Andrew exchange quotes from "The Coming of the Ship" by Kahlil Gibran. Ruth misattributes the words to Abu Nuwas. This may be her way of testing Andrew's knowledge of Arabic poetry. (He does not catch the error.)
Nicola Walker (Ruth Evershed) and Adrian Rawlins (Andrew Forrestal) both worked on Prisoners Wives (2012) as DCI Jo Fontaine and Ian, respectively.