These artifacts make her look like a cyborg with her face peeling off
Totally breaks the immersion.
Nefastus, this is usually caused by the hair acting up or inadvertent parenting issues. You won't see it in the texture shaded viewport - only with Iray, so it's a sneaky bastard. If it is showing up in some renders and not others, you'll probably notice that the model is not in the same coordinate location, which matters for some reason.
You can usually fix it permanently by reducing the forehead depth slider, the scale of the hair cap or playing with the hair volume. I saw it happen once where it required creating a shaping preset for the character and just rebuilding it quickly off that preset, taking care that any hair morphs or eyebrow morphs have the hair/eyebrows selected when applied, not the character. Just tweaking the forehead depth should fix it going forward, though.
You likely already know, but you can get rid of Christine's forehead artefact in Photoshop or Gimp simply with the spot healing brush, on already rendered scenes.
