The problem really wont go away except by shooting under higher exposure/lower shutter spped if your camera allows it.
Try adjusting brightness, contrast & sharpen as well as denoise and you maybe will get a better result. I find that simply brightening the clip and THEN denoise has worked in the past.
Alternatively you simply add a banner at the beginning saying "This movie was shot under available light conditions so that the performers would not be distracted by my presence...." or something like that.
Remember great content is always going to be interesting even in low light, ask any senator caught in his car with a girlfriend.
If you can't solve the problem - Change the problem