The main characters entered a tower where it is rumored that the tower's guardian turns any intruders into a doll. All of them ended fighting a somewhat comedic battle with a monster called Joe, where the losers got turned into dolls. 2 female characters got transformed.
The series Slayers NEXT started in 1996 as a continuation to Slayers which ended in 1995. This episode shows Martina and Amelia got turned into dolls with the other three characters.
It is unknown if the dolls and marionettes shown at the early and middle part of the episodes was the 'victim' of the tower itself, although it did mentioned that any intruders into the tower will get turned into dolls. Joe, the monster also is a doll collector itself.
The face expressions of the dolls seems changed in different panel, with the prominent one is the 'smile' on the doll's face.