If you shot in daylight, you can still fake Neon Dark in post-production (DaVinci Resolve or Premiere Pro/Lumafusion).
This is the secret sauce. Reflections double the neon. Pour a little water on the floor, shoot into a mirror, or use a glossy table. The reflection of the neon light on a wet surface immediately adds cinematic depth. neon dark video
You do not need a $10,000 cinema camera to achieve this look. In fact, modern smartphones are exceptionally good at this specific genre because their sensors handle high contrast well in video mode. Here is the essential gear ladder. If you shot in daylight, you can still