Sketches of the man - drawn at the request of The Independent by a professional artist in separate sittings with Samar Alami and Jawad Botmi in their prisons in the north of England - show an almost identical image: that of a dark-skinned man in his 40s with a lined face, short, black fringe, prominent eyebrows and nose, and staring eyes.
At their trial and in the two years since, Alami and Botmi have protested their innocence of the bombing, insisting that the explosion in July, 1994 - in which, remarkably, no one was killed - could only harm the Palestinian cause.
In his summing up before their conviction in 1996, Mr Justice Garland remarked that, so far as the two accused were concerned, Moghrabi "could have been a Mossad agent or a police informer..."
The police agree that Alami and Botmi did not actually carry out the bombings but - save for a look through immigration files - have made no further attempt to find Moghrabi. Alami and Botmi were sentenced to 20 years. They were also convicted of conspiring to bomb a building containing the Zionist Federation office in Finchley, north London, a few hours after the embassy bomb - though both proved they were far from the scene of the explosions.
Even before the trial began, however, the Israeli ambassador "congratulated" the police on their arrest of the "terrorists". Strangely, an Israeli embassy security video-camera that might have identified the faces of the real bombers was "not working" on the day of the explosion.
Alami first disclosed Moghrabi's name towards the end of the court hearing - 200 hours of evidence that contained enough errors and interruptions to raise serious questions about the convictions - and insisted, with Botmi, that she knew nothing about the embassy attack. Today they are convinced, in Alami's words, that "Moghrabi or someone with him set us up from the beginning, either deliberately or to protect themselves from being caught".
Moghrabi - who must have been well known to dozens of Palestinians in London where he attended political discussions and poetry readings at meetings of the Arab Club - apparently worked in the Gulf in the late 1980s and settled in Kuwait until fleeing when the Iraqi army invaded in 1991.
Alami said that she heard rumours that he may have married an English woman in Birmingham; she remembers being given his telephone contact with a prefix 021 (then the dialling code for Birmingham)but says she did not keep the number.
At their 1996 trial, neither Alami nor Botmi - respectively chemical and electronic engineers - attempted to hide their own dabbling in experiments which, however preposterous, were intended to assist Palestinian groups in Lebanon and the occupied territories.
They admitted trying to construct miniature aircraft that would carry bombs across the Lebanese frontier to Israel - in the course of an experiment in the Peak District they almost blew up a tree.
Alami was also found in possession of explosives as well as two guns which she said she was keeping for a Palestinian who feared assassination in London.
Bomber who never was,