Travis Clark’s review published on Letterboxd:
Knowing little about this one I expected more of a straightforward Hollywood thriller, so color me pleasantly surprised when I got a movie more in line with Jean-Pierre Melville and Costa-Gavras. A process film where we watch the desperate French Foreign Legion reach outside the country for a hitman who may be able to get close enough to President Charles de Gaulle to assassinate him, while also watching the intelligence community attempting to figure out what is going on and to stop the potential assassin from entering their country.
Here the assassin goes by code name The Jackal (Edward Fox) and we watch as he goes through the process of negotiating his fee, picking up the necessary papers (from Ronald Pickup), ordering a custom firearm (from Cyril Cusack), romancing a married woman at the hotel (Delphine Seyrig), acquiring vehicles, crossing borders, cleaning up witnesses, and everything you might expect a professional hitman to have to deal with, and maybe a few you may not. On the other side of the law is French detective Lebel (Michael Lonsdale) and a well cast rotating group of intelligence men from France and elsewhere, as they try to figure out which assassin the Foreign Legion may've hired, and how and where to track him down, all as their outgoing leader refuses to cancel public appearances.
I also liked Zinnemann's choice to stick to only diegetic music after the first five minutes, only adding to the realism and intensity, and the cold precision of the Jackal, emotionlessly doing what he must to evade capture and follow through with his objective. I must say though, that with the best of Melville and Costa-Gavras I never feel the length, but I was beginning to feel the 143 minutes by the end, and unlike those filmmakers' best, I'm not sure if this movie adds up to anything more than the sum of its parts. A well made, engrossing process crime film and nothing more.