These dark specks are called floaters. Floaters can be very common; however, when they suddenly appear in this manner and especially if they are associated with flashing lights, a complete dilated eye exam with an ophthalmologist is indicated as soon as possible.
The reason an eye exam is needed quickly lies in the fact that these could be signs of an impending retinal detachment. The retina is the back of the eye and when it becomes detached the vision could be affected permanently. Usually there is a window of 24 to 48 hours to preserve vision if a retinal detachment is diagnosed.
I would like to point out that floaters and even flashing lights can frequently happen while retinal detachments are relatively rare. Still, the eye exam is indicated to diagnose the condition accurately and if nothing else to offer some peace of mind.
I hope this helps and that your wife is well...