TIME'S Sue Johnston has admitted the BBC drama is 'frightening and horrendous' after the first episode left viewers shaken. The three-part series began on BBC One on Sunday night and stars Sean Bean as Mark, a mild-mannered teacher who is jailed for killing a man after drink-driving.
The series also stars Stephen Graham as a prison guard who faces his own conflicts, as well as Sue, who plays Mark's mum. The first episode featured bullying, violence and a suicide, leaving viewers shaken and obsessed in equal measure.
Appearing on today's This Morning to discuss the drama, Sue, 77, admitted she also found it a tough watch despite being in it.
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