Cross (Burt Lancaster) is an old hand at the assassination game: he taught Scorpio (Alain Delon) everything he knows, which is plenty. He works for the C.I.A. in making sure American foreign policy is enforced with as much muscle as is necessary, in their view at any rate, and their latest job is to target a Middle Eastern leader who was getting too big for his boots, even though he was on the United States' side, which seems a fair job for them to carry out. But it triggers more than unrest internationally - it also means Cross knows too much.
And what do they do with men (or women) who know too much? Well, you can guess that Cross is not long for this world seeing as how he is mixing with some very murderous people and has been since before the Second World War, but it is Scorpio who is ordered to take him down, which in theory should have led to the sort of suspense engendered to a reasonable degree in director Michael Winner's The Mechanic a short while before, but actually in this case developed into what could best be described as murk and lots of it. We were in John le Carré territory here, except it wasn't enough to have the characters discussing their situation in gloomy rooms.
Therefore we also got some action sequences into the bargain, which had the effect of waking up those in the audience in danger of nothing more than nodding off thanks to the somnambulistic pace Winner had lent proceedings. So rather than deepening the intrigue, the general effect was that you would begin to reject the spy shenanigans as so impenetrable that it wasn't worth the effort to work out why this character wanted this other character dead, and this one wanted both of them dead, and someone else... You get the idea, and this cynicism could have badly done with a sense of humour.
As it was there was far too much despondency which not even the admittedly well-staged action could compensate for. When Cross discovers he has a price on his head, he goes underground, as if he were not far enough underground already, and meets up in Europe with his Soviet opposite number Zharkov, played by Paul Scofield - there's another respected Shakespearean thespian on the Agency's side in John Colicos, although he's probably beter known for being the original Baltar in Battlestar Galactica. Worth mentioning is that for reasons best known to themselves the actors pronounce Schofield's role's name as "Jack-off", which is unfortunate if nothing else.
Anyway, the succession of terse, meaningful conversations about everyone's impending doom does grow wearing, particularly as by the end it appears nobody in the film was innocent except perhaps the cats Scorpio is preoccupied with, his chief personality trait in light of having little else to demonstrate he's not all bad. For Lancaster, apparently he wasn't too pleased with this movie, but he does his usual professional job and you can imagine him relishing the chance to discuss motivations at great length, either with himself or anyone he could get to listen. Even at his advancing years, he proved himself a convincing man of action, and his sheer physical presence goes a long way to filling in what the script failed to sketch out adequately. But mainly the trouble was this was so deadly (literally) serious that while the hardened espionage movie fan could get something out of this, the alternative was that Scorpio was pretty dull overall. Music by Jerry Fielding, sounding as if this was more exciting than it was.