You know what has always killed me about this scene? It’s a combination of him realising that he knew the ‘man on the bridge’ and being so helpless as to stop Hydra from taking away his memories (again), his screams of pain and more importantly, the fact that before this scene, he is the Winter Soldier. A ruthless killer with no emotions or fears. And then you see his hand trembling and the deep shaky breathing, just waiting for the excruciating pain that he’s about to be put through. For a couple of seconds, you don’t see Winter Soldier, the ruthless killing machine on your screen; you see Bucky Barnes, helpless, scared and about to be brainwashed.