When I was kid in the late 90s I remember seeing just the end of this movie or TV show. People were getting chased in this underground facility by a naked mutant man. He hissed a lot and had sharp teeth. A explosion went off and a copter was was waiting for the people ate the exit. As they were climbing up the ladder the copter dropped down, the mutant man looked up out the exit and let out a vicious scream. Then happy music played as the copter flew off not knowing the mutant was on the sides of the copter. That's all I remember.. I've been looking for these movie/show for years.