Chris Pine portrays the central figure, a US intelligence operative who lives through a helicopter crash in the Mediterranean before being brought into a Langley organization by "Harper" (Kevin Costner). His assignment involves looking into questionable financial dealings, which leads him to uncover what "Cherevin" (Kenneth Branagh) is doing—apparently falsifying records and diverting considerable funds. The explanation, according to those who speculate on such matters, is that this is all part of a scheme intended to undermine the dollar and financially ruin the United States. “Ryan” is then dispatched to Moscow, but this presents difficulties: he’s essentially an office worker and hesitant about active duty, plus his girlfriend "Cathy" (Keira Knightley) is suspicious of what he's involved in. Regardless, he heads into a dangerous situation, and before he can figure things out, she unexpectedly shows up, and soon they are both targets of the unpleasant Russian and his seemingly endless group of henchmen who seem incapable of hitting a major landmark. Pine performs acceptably, and Branagh does alright despite his accent—though Costner feels rather lifeless, and Knightley is simply not good. She generates an irritating character from beginning to end as the narrative progresses through increasingly improbable situations. The ending moves quickly but feels disorganized, and I was let down by how straightforward and mechanically executed the entire story turned out to be. It’s passable, but it doesn't compare favorably to the Harrison Ford versions.

Source on TMDB