FAQ for
Ronin (1998) More at IMDbPro »

The briefcase is a "MacGuffin" - a term director Alfred Hitchcock and writer Angus MacPhail coined to describe a plot point that is deliberately left vague so as not to draw too much emphasis away from the real story.

If you really want to narrow down the possibilities:

1. It is worth more than $800,000 (the maximum the Irish are willing to pay the mercenaries since they cannot afford to bid for it, and about the same amount that can fit in Gregor's briefcase at the end of the film);

2. It is wanted by both the Russians AND the Irish, but neither is willing to pay for it;

3. It is small enough to fit inside an ice-skate case, but not too heavy to be man-handled by a variety of characters; and

4. It cannot be hazardous material, since Gregor was able to mail it to himself through the French postal system, who would check.

Some speculations are:

1. Important (stolen?) blueprints;

2. Printing plates for the new (at the time) Euro bills;

3. Important, probably stolen, documents.

4. The ice skate case belongs to the Russians and contains information that they want back. (Details of arms sales? Pictures of Mikhi with underage boys? Who knows.). That's why Mikhi wants it back but doesn't want to pay for it: handing over money could validate the contents and be used to blackmail him later. The Irish want it as leverage over the Russians. The CIA want it to convict the Russians. The man with the case wants to sell it and make a quick buck.

In the end, the contents of the briefcase are irrelevant since the case's only real function in the story is to give everyone a reason to be running around France getting into gun battles and car chases. Director John Frankeheimer says as much in the DVD commentary.

Sam uses a .45 Mil-Spec 1911 handgun, a 40mm HK69 grenade launcher, a SIG 551 assault rifle, a LAW rocket launcher, a FN MINIMI light machine gun, and a .45 SIG P220 handgun. Deirdre uses a 9mm Jericho 941 handgun and a 9mm Heckler & Koch MP5 submachine gun. Spence uses a HK USP handgun and a 9mm HK MP5k submachine gun. Vincent uses a 9mm Beretta Inox. Larry uses a Remington 870 pump-action shotgun and a nickel-plated 9mm Taurus (Brazillian copy of a Beretta 92). Gregor uses a 9mm Glock 34 with sound suppressor and EOTech holosight.

Gregor, Sam and Dierdre make reference to "The Man from Bristol." His given name is never revealed. From what is mentioned in the film he is apparently a retired intelligence agent who was paralyzed during the Cold War and confined to a wheelchair. He currently works as a sort of employment agency for mercenaries. Dierdre hired both Sam and Gregor through The Man in Bristol. His nationality is unknown but presumably he is not from a Soviet Bloc country since, when Gregor asks how the man became paralyzed, Sam states that it occurred "in your neck of the woods" (ie East Germany or the Soviet Bloc).

The female sniper is most likely just another mercenary, perhaps one of Gregor's ex-KGB acquaintances. The identity of the sniper was probably another element of the plot that was purposely left out, just like The Man In The Wheelchair or the contents of The Briefcase.