In Another Job for Biggles, Nicolo Ambrimos, also nicknamed "The Sultan", was a wealthy merchant living in Aden who was Biggles' chief adversary and a major character in the story.
According to Captain Jerry Norman, Biggles' local contact in Aden, Ambrimos was a very successful businessman who dealt in all kinds of commodities but chiefly in incense. He owned several dhows which ran a useful transport service among the smaller Red Sea ports, carrying general freight and trading in produce such as dates from Muscat and coffee from Mocha. There was even talk that he planned to start an airline. Norman added that there was a rumour that his success and wealth really came from dabbling in hashish, a narcotic, also nicknamed "honey".
Biggles' attention was drawn to Ambrimos because, according to one of Norman's contact, he had been seen with Abu bin Hamud, one of the three Arab guides who accompanied Doctor Guthram Darnley on his expedition when he had discovered the powerful narcotic "gurra" at the Wadi al Arwat. As a dealer in hashish and a merchant who wanted a part of every lucrative venture, it was highly probable that Ambrimos would be interested in getting his hands on gurra. All this as proven as Biggles later found that not only did he deal in hashish--Zahar admitted smuggling this for him--but he actually grew it himself at a farm at El Moab. There he had also began cultivating a small patch of gurra. Whether it was Ambrimos who sent Abu bin Hamud to collect the gurra seeds from Wadi al Arwat and then burn the shrubs, or whether it was Abu's own initiative to do that and then sell the seeds to Ambrimos was never established in the text.
Norman did not know what nationality Ambrimos was but described him as Levantine of very mixed parentage. A charming man of around fifty, he spoke English well and claimed to have studied at Oxford. He was also what Norman would call "elegant", particular about his appearance, dressed in expensive clothes, and lived in one of the best villas in Aden, the Villa el Paloma in the Stretta Fontana which used to belong to an Italian count.
Biggles' first meeting with Ambrimos left him with the same impression of the man that Norman had, and was also the opportunity for another one of Johns' extensive descriptive word pictures. Among other things, Ambrimos was fifty "with that unhealthy stoutness that so often goes with that age in the East". He had a round face, was clean-shaven, a skin of "curious intermediate tint", black hair that "gleamed like patent leather". He wore European clothes, comprising a frock-coat, pin striped trousers and patent leather shoes. A massive gold watch-chain hung around his paunch.
Biggles concluded that Ambrimos was "typical of a type fairly common in the Middle East"--shrewd, self-centred and utterly unscrupulous. When he learnt from Biggles that Zahar had been seen in Aden after being left for dead in the desert, he did not hesitate to try to silence him. Later, when Ambrimos met Biggles again at El Moab, he tried to bribe Biggles to drop the investigation and work for him as a pilot--a strategy which he called "buying a road". When Biggles asked how he could be so sure that he would not betray Ambrimos by pretending to work for him and then selling his secrets to the authorities, the Levantine replied that this was exactly what he himself would do, but he took advantage of what he considered a weakness among the British, that they never went back on their word once they had given it. When his attempt at bribery failed, Ambrimos revealed that he had political, if not megalomanical tendencies, vowing to bring down the British empire with gurra. Biggles observed that he was "another wold-be dictator burning to inflict his will on a world still suffering from the effects of the last one".
Ambrimos was believed killed at El Moab after Bertie blew up the irrigation dam there, releasing a flood of water which also eliminated the hemp and gurra crops. According to Captain Norman, although no one seemed certain what had happened, Ambrimos was never seen again at Aden or any of the Red Sea ports where he conducted his business and his commercial empire collapsed.