The only similarity is the title.share
Actually...I just watched the two versions back to back. The remake stays very faithful to the original.
Losey had the original script updated in it's time and place,and rewritten, but every major plot point and character have their roots in the original. The ball bouncing Elsie, the whistled tune, the blind balloon seller, the police chief and the the "organization," the police raiding his room, getting locked in a room in a big building, the "organization" going on a manhunt, the mob trial and defense. All the plot points rewritten, but there. All the characters.
Granted that Losey was no Lang, but this was a very credible and faithful remake.