The team notice that DNA from teen-aged market trader Spencer Rogers, arrested for throwing a brick on the motorway, matches that of interpreter and chess club member Agnes Bradley, murdered in 2010 and when Spencer's mother Kelli tells Sasha that Spencer was the result of her being raped by an unknown man it is apparent the rapist is the murderer. Suspects include Jeremy Powell, who, according to chess club captain Viktor Proust, smarted because he could never beat Agnes and Chilean diplomat Carlos Alvarez who had Agnes black-listed after one of her translations warned students against his womanizing. Whilst the rest of the team is busy trying to catch the murderer Steve is occupied with bringing his hate-filled dying father Robbie to a hospice in London.