i have only checked season 2 because they get trouble with a shapeshifter and getting tied up by a double is a famous treatment scene.
Ep 9, a robot capture 2 students

Ep 16, 1 of the students get a handgag

Ep 17, part 2 of a 4 part episode.
In this episode students get captured by a spider monster, he webs up students but when they get entire webbed up they turn into spiders





Ep 18, continues from ep 17




