You can make noon look like midnight, if you know how to use strobed light.
I remember seeing some of your work, so what is your secret
There is no secret to it.
Having an understanding of how a camera works helps a great deal though.
What happens when you set the aperture to a small lens opening, ambient light wise? Not much light gets in.
The fastest shutter speed that can sync with strobed light at full power is 1/200 or 1/250 depending on the camera, or if the camera has the feature you can use FP/HSS sync mode and use any shutter speed that is faster than the normal sync speed.
With dSLR's you have 2 choices for when strobed light fires. At the begining of the exposure (front/first curtain sync) or at the end of the exposure (rear/second curtain sync).
Think about what happens in each situation and investigate how long a burst of light from a strobe lasts based on it's power setting.
For a a Nikon SB-600 has a duration of the flash at
1/1 power = 1/900
1/2 power = 1/1600
1/4 power = 1/3400
1/8 power = 1/6600 (faster than the fastest shutter speed D3000/D5000/D90)
1/16 power = 1/11,100 (faster than any Nikon shutter made)
1/32 power = 1/20,000
1/64 power is 1/25,000
So, with a small lens opening restricting the amount of light getting in, the shutter set to the normal sync speed (1/200 or 1/250), the camera set to rear/second curtain sync, flash set to full power, the flash takes over the function of the shutter and can stop motion since the duration of a SB-600 is 1/900 or shorter.
The shutter speed then actually controls the background exposure, rather than being a means to stop motion.
You control the exposure of the subject with the speedlight power output and/or the lens aperture.