August in Edinburgh: As Skinner stands on the edge of a career-defining moment and his fiancee, Scotland's First Minister Aileen de Marco faces a political crisis, a famous figure from another field is found dead. As the mystery deepens, Skinner finds himself crossing swords with an old enemy from the past, while his investigating detectives are faced with the unwelcome complication of a duke's junkie daughter. Meanwhile a second Scottish celebrity dies violently in Australia. It seems impossible, but could the two be connected? As DCS Mario McGuire heads to Melbourne to investigate, back in Scotland his boss's big moment is compromised in the most dramatic and unexpected manner, as a famous friendship is shattered for ever.