fast one n.
1. [1920s] any scheme seen as amoral, corrupt, underhand.
2. a lie, a spurious story.
1. [1920s+] (also spring a fast one, pull a fastie, work..., pull a fast switch/shuffle) to get away with something, usu. a slightly nefarious scheme.
2. [1930s] to stage a crime, e.g. a hold-up.
3. [1930s] to make an escape, to run away.
[1920s+] to take advantage of someone by trickery, to hoodwink.