Unman, Wittering and Zigo (movie)

Unman, Wittering and Zigo is a 1971 British thriller movie. The movie was directed by John Mackenzie. It is based on the 1958 play of the same name. The movie stars David Hemmings, Douglas Wilmer, James Warwick, Carolyn Seymour, Hamilton Dyce, Anthony Haygarth, David Auker, Hubert Rees, Michael Kitchen, Tom Owen. It was distributed by Paramount Pictures.
Plot.
The movie is about a new school teacher who learns that the former teacher was killed by the students. The teacher worries that the students will also kill him.