She certainly has acted like a fly-by-night up to this time.
He'll be out with a fly-by-night troupe afore the next month.
Shown up in our newspapers as a ditch-digger—a fly-by-night—a nobody!
Had the wind been directly astern, the course of the Fly-by-Night would have been smoother.
Torched on by that fly-by-night who'll be getting out of town and who'll be forgotten inside ...