This is the second Omnibus edition featuring the young Probationary Detective Constable McNab and his ghostly mentor and companion, Dr. Joseph Bell, expert in deductive reasoning and forensic medicine and the real-life model for Conan Doyle's Sherlock Holmes. In this edition there are again three case studies set in and around Edinburgh, Scotland: The Selkie of Calaroin - McNab's boss, Chief Inspector McFarlane enlists McNab's help in a personal matter when he is asked to go to the small fishing village of Calaroin by his old friend, Angus Dunsmuir, the local Police Sergeant. A young fisherman has been found dead in his bed with the local doctor giving the cause of death as cardiac arrest. Sergeant Dunsmuir has doubts about this and has asked McFarlane, who had been born in the village, to unofficially look into the matter. McNab and Bell find that the young fisherman had really died of drowning. But how?The Blue Claidh - McNab's love interest, Detective Sergeant Olivia Kerr has gone missing. Only a small sample of blue clay (or claidh in Scottish terms) in an old Case Box from Glasgow Police may give a clue to where she has gone. He goes to the Earth Science building at Edinburgh University to find the location of the mysterious blue claidh without success, but his ghostly friend DR. Joseph Bell enlists the aid of the spirit of the very 'Father of Geology', Dr. James Hutton to assist. Finding the location of the clay near the town of Melrose, McNab finds Olivia as a prisoner of a gang of Glaswegian bank robbers planning their next crime in Edinburgh. He and Bell go to her aid against the gang.The Dominie's Downfall - Set in the old manor house of McGovern Hall near Thornhill northwest from Edinburgh and now Saint Triduana's School for Young Ladies. McNab and his driver Sergeant 'Jock' McDonald are sent to investigate the death of an unpopular teacher - a Dominie in Scot's slang - who has fallen down a stairway and broken her neck. A simple unfortunate accident which soon becomes a murder case when someone states that the teacher had been pushed. But nobody at the school was near the stairs when the woman fell and so accidental death seems to be the only obvious conclusion. However, the ghost of Joseph Bell come to McNab's rescue again and confirms that the woman was really murdered and helps the detective solve the case.