GoldenEye 007 became one of the most important games in the N64's lineup, as well as a hugely important part of game history overall. The experience was absolutely amazing for the time, and provided countless hours of fun in both single and multiplayer. That entire groundswell of support likely wouldn't have been anywhere near as big if the game's original plans went forward.
The above trailer showcases the original design for GoldenEye 007, which was going to be an on-rails shooter. Bond would simply walk a scripted path, and you'd shoot along the way. Thankfully the team decided to go full-on FPS somewhere after this, and the rest is history!