The BBC hung onto live (multiple cameras to tape) drama longer than most, partly because this gave them a measure of independence from the unionised film laboratories. After the sensation caused by his 1984, Rudolph Cartier was it's undisputed master.
It is hard to imagine any other set-up producing something as ambitious and thoughtful in this format in 1968. It's speculative as to whether there was a need for a historical drama about an over zealous prosecutor torturing a Hugenout family, because he thought they killed a son who wanted to abjure their religion, with language given such careful and exact emphasis. Badel as the apparently reasonable and thoughtful evil doer gets one of his best outings and the intelligence of the work is never in question.
Cartier's use of the confining form is, as always, imposing. His best work should be widely circulated. It compares favorably with the output of feature film makers.