What is the name for old Showtime b rated horror movie?

I am looking for a Showtime movie I saw years ago. A bunch of teenagers leave a cave where survivors of a scorched Earth were. They venture across a desert and wind up passing out. Near dead, they are supposedly saved by a couple that turns out to be aliens. The guy looked like a punk rocker and the girl was a super hot Thai or Philippine girl. The couple seduced the teens one by one and took over their minds by having sex with them. Think it was something called Alien's Attack or When Aliens Attack. Not sure of the name.