Professor Philip Mortimer has decided to spend his holidays in Cairo with his trusty servant, Nasir. There he plans to meet his old friend, Professor Ahmed Rassim Bey, who offers him the fantastic opportunity of satisfying his passion for Egyptology. Professor Bey has invited him to take part in deciphering his latest discoveries—in this case, some papyrus coming from mummies of the Ptolemaic age. Mortimer and Bey soon realize that one of the fragments deals with the “Chamber of Horus,” a fabled crypt that could contain priceless treasures...

Captain Blake seems to have lost the first round in Part 1, having been assassinated at Athens airport. But a furious Mortimer swears that he'll never stop trying to avenge his friend. He goes on the hunt, but information is scarce. Strange happening occur when he comes under the protection of Sheik Abdel Razek and Mortimer soon feels like he's losing his way in his investigation which will lead him to the darkest depths of the Great Pyramid...

Blake and Mortimer head to the United States to investigate the mysterious circumstances surrounding the discovery of a 177-year-old body, which appears to have died very recently. The body is that of a Scottish major, Mortimer’s forebear, who was leading a British military expedition to the US in 1777, where he was swallowed up by a strange multi-coloured light-beam shining down from the sky. Blake and Mortimer fight men in black armed with green-laser guns and soldiers emerging from the past in order to save the Earth from complete obliteration.

A necklace that used to belong to Marie Antoinette, the last French queen before the French Revolution, turns up in the hands of a British collector who decides to present it to Queen Elizabeth. Blake and Mortimer’s sworn enemy Olrik, about to be tried in Paris, manages to escape and steals the precious piece of jewellery in front of their very noses during a glittering reception in the French capital. The affair threatens to turn into a full-blown diplomatic incident, especially since Olrik is doing his best to embarrass Blake and Mortimer by tipping off the press about his every move.

A Soviet rocket falls back to Earth carrying deadly bacteria. KGB Professor Voronov turns the extraterrestrial threat into a terrifying weapon that could be used to devastate the Western world–but he doesn’t take into account the vigilance of Her Majesty’s intelligence services. Soon, Blake and Mortimer are drawn into a lethal, shadowy war, from Moscow to London, where the stakes are no less than international peace and the real enemy may not be so obvious.

Several months after their adventures in Antarctica, Blake and Mortimer are back in England. Still somewhat shaken after his ordeal, the professor is ordered by his doctor to get some rest. In typical Mortimer fashion, he decides to spend his holidays in Africa... looking for a lost civilisation! Accompanied by Nastasia Wardynska and an old flame of his, he begins tracking down a culture that is older than any ever recorded—but someone is dogging their every step...

Deep under Sao Miguel island, rumoured to be the last emerging part of Atlantis, Professor Mortimer has discovered samples of a mysterious radioactive metal. Could it be the Atlanteans’ legendary orichalcum? When he and his friend Blake set out on an expedition into the depths to find out, sabotage occurs in the form of their old opponent Olrik. And soon, all three will be embroiled in a power struggle far bigger in scope than they could have imagined.