So it doesn't get any better. They were trapped in that mirror dimension for all of two minutes, and vanquished the demon in 2 seconds by using selfie mode on the camera.
Also, a truth serum isn't equivalent to verbal diarrhea. The person who ingested it would be forced to answer questions truthfully and unable to lie, but this show's take on it was just so hokey.
I'm quite disappointed by this weak reinterpretation of Charmed.