She published two novels early in her life, then taught for 10 years in a London comprehensive school, before going on to have a distinguished career as a psychotherapist. When she was diagnosed with cancer and retired, she returned to her first love of writing fiction. Hidden Knowledge is part of that late flowering, and in it she draws on her experience as both a teacher and a therapist.
There is no one main character in this novel; the action focuses on three unmarried siblings, Roger, Romola and Hereford Tree. Roger is a recently defrocked priest who has been accused, and has admitted to, the sexual abuse of a 14-year-old boy, but his confession masks a much darker secret. On bail and awaiting trial, he takes refuge in Romola's house, while she is caught up with her older brother Hereford, a well-known novelist who has suffered a cerebrovascular accident during heart surgery and is severely brain damaged and in a coma. Romola is also a head teacher coping with the stress of her work and an Ofsted inspection.
All three characters are brought to life vividly as flawed, ordinary people. Roger is all too human in his capacity for what he himself sees as sin, yet as a priest and a Christian he is unable to delude himself indefinitely that his actions have done no harm, and Bishop puts him through the moral torment he deserves, making him confront some anguished choices. Romola undergoes the moral dilemma of whether or not to change the grim, hopeless ending of her brother's recent, unpublished novel before sending it to the publisher. Carina, Hereford's young, beautiful Italian wife, stands to gain a great deal if Hereford dies, but she is no gold digger and genuinely loves him, and she hates to see him in a vegetative state. So she finds herself paralysed with indecision when she is faced with the moral conundrum of whether to alert the emergency staff in the hospital when he has a heart attack in her presence.
Alongside this family in crisis, in what at first appears to be a sub-plot but comes to be more central, is another family rocked by a tragic event.
Betty Winterborne, who is still grieving for the loss of her young son in a tragic accident at school camp many years ago, has now lost her husband and is trying to face the thing she dreads most - loneliness. Her daughter Julia, a successful 38-year-old psychotherapist, is too busy with her career to offer much support, though her career success does not diminish her regret at being childless. Interestingly, when she does something about that and decides to move back into the family home with the baby, what everyone assumes will be a godsend for Betty turns out not to be: "Left alone, Betty sat with her hands folded on her lap, thinking, and unable to rejoice. Her engagement with her loneliness had taken a great deal of energy and courage. Proteus had changed shape often, and, despite pain terror, she had hung on. Now he was ready to tell her the truth, and the truth was that she was able to be alone. And now, already, that hard-won, barely tried capacity was to be taken from her."
In a brilliantly controlled plot, both these families' stories gradually mesh together, leading to the shocking revelation of a dark secret at the end of the novel.
Bishop is not afraid to tackle subjects many writers would regard as taboo - her last novel Unexpected Lessons In Love dealt with bowel cancer. In Hidden Knowledge she probes the tricky moral territory of paedophilia and clerical abuse, not to mention the ethics of artificial insemination and the use of life support machines for people who have no hope of recovery, and she leads us through this moral minefield with admirable candour and assurance. Hidden Knowledge is nothing if not topical in its treatment of these serious moral issues, but it is also very funny and poignant and immensely enjoyable.