Pilot Pen Corporation recently released the friction line of erasable gel pens. When the writer wishes to erase a mark, the friction caused by the rubbing of the eraser end of the pen generates heat at or above 140 degrees F. This chemically alters the composition of the ink, making it colorless to the naked eye. The colorless writing can be restored by subjecting it to temperatures of 14 degrees F or cooler. This article examines the effects of latent print processing and DNA swabbing on Pilot's thermo-sensitive gel ink, the utilization of liquid nitrogen to restore the ink's color, and suggested screening methods for detecting intentionally concealed writing. (Published Abstract)