Tosh visits the Sadats to ask if Ellen's struggles might be related to their son's death. They maintain that Ellen barely knew Akmal but, after Tosh leaves, Farida begins to unravel as her husband Azir watches on, concerned.
A voicemail from the night before turns suspicion onto Bobby Bain, but Tosh resists Calder's demands to make an arrest. When Sandy finds evidence of drug dealing at Cal's house, a defensive James points the finger at Neil Bain.
Tosh is accused of harassing the Sadats and Procurator Fiscal Harry tells her to back off. However, the warning only deepens Tosh's suspicion. Combing through the case files, she discovers evidence of a surprising connection between Heather Bain and the Sadats' family tragedy.
Later, a surprise confession reveals the shocking next step in the final movements of Ellen Quinn.
The season is not bad, but I think the new detective, is terribly annoying for me, Tosh is a hundred times better character and investigates better, there is no reason to make her the boss in the next seasons. I don't even understand how her colleagues tolerate her lying to them continuously, she should have been removed from the case and from the island a long time ago. I hope they make Tosh the main detective and the series continues with her and her team.