Something terrible has happened to Henry Knight; Sherlock and John investigate the truth about the monstrous creature which apparently killed their client's father. A hound from hell? What seems like fantasy in Baker Street is a very different prospect in the ultra-secret army base that looms over Dartmoor.
When a middle-aged Oxford graduate is found dead near his run-down Oxford house-boat, detectives Lewis and Hathaway are thrown into a delicate murder case which implicates one of the University’s most prominent figures.
A chance encounter means Luther might be on the verge of finding love. But nothing comes easily - not when a fetish killer is on the hunt, not when an internet tormentor has had the tables turned and not when his worst enemies are his own colleagues.
A visit to ancient Rome puts the Doctor and Donna in Pompeii just ahead of what the Doctor calls "Volcano Day".