The script held in the Crawford Collection in the AFI Research Collection contains the following character notes (excluding regular characters):
'VICTOR RYDER: Age 25 or 26. A junior sales executive with a city company. He's of above average intelligence, comes from a rural background and is part aborigine - although this doesn't show in his appearance. He is a man who has always believed he had to do a little more than others in life because of his "touch of the tar brush". Normally he's a quiet, introverted person who enjoys periods in the wilds, fishing and hunting etc. This communion with natural things is not, however, a dominant part of his life, but is kept in proportion. He has married Susan, a city brought up lass and is very conscious of his added responsibilities. He is working even harder to gain the security they both need. We see him at his worst - a man under pressures alien to his nature. When he cracks his intelligence allows him to nevertheless display a biting cynicism towards the crisis. During the siege we should deplore the things he says, but yet our sympathies are with him. With his savagery he should shock us - his moods bewilder us and yet we should be able to have empathy for his predicament.
'SUSAN RYDER: Age 22 or 23. In most ways an average young lady. She met Victor at the office and they married after a short courtship. She is of average intelligence, but had been fairly close to her father before his death some years earlier. Victor represents the security she needs because of his driving ambition to succeed. She doesn't really know why she agreed to lock Victor out at the request of her mother and the "church". The two represent a stronger authority than Victor and that's that. When given time to see the "truth" she is glad to do an "about turn".
'CELIA WATSON: age 40-42. We don't see much of her and yet she is very important to the story. She's the mother of Susan - A widow. After her husband's death in an accident she has sought emotional security in a socially acceptable way - not with another man - but in church work. She has become under [sic] the dominance of the Sect's leader, Gardiner Adams. The tenets of the group are extremely strict and these reinforce her own moral inclinations and prejudices. Discovering Victor's ancestry has allowed her to use this to force Susan to lock him out. She has felt unimportant in Susan's life since Victor came along.
'GARDINER ADAMS: 35. Not a big man physically, but a magnetic man with a compelling presence and a rhetorical power that sways his "flock" to his way of thinking. Before founding his "Shepherds of Life" sect in Australia he spent several years overseas and his sect and it's [sic] moral codes are an amalgam of Eastern and Western moral strictures. In dealings with his followers he exerts an almost hypnotic influence. He ajures [sic] his followers to abstain from all drugs (including coffee and tea) from watching television as an agency of sin - from gambling. One of the prime sexual crimes is miscegenation. The trouble with Adams is that he's number one among the country's hypocrites as well as being quite a successful con man and filling his pockets from the tithes imposed on all members. He uses his personal influence to do what he wants. Susan is the first of his "sheep" to wake up.
'SARAH ADAMS: Age 30-35. Adams' wife she is straight laced and has complete faith in her husband and his teachings. She has no idea of the duplicity of his practices and if she found out her mentality is such that she'd refuse to accept it.
'JOANNA WILSON: Age 24. Member of the "Shepherds of Life" she came under Adams' observation and interest when she attended a meeting out of curiosity. Quickly drawn in because of her idealism she has become yet another of his conquests and leads a life of moral hypocricy [sic] - outwardly complying with all the sect's doctrines while she maintains her adulterous liasons [sic] with Adams. Give her this much, when she sees that Adams has another "kill" lined up, she shows quite a bit of intestinal fortitude.
'BENNETT SHIEL: 30. Victor's immediate superior at work. He is about as close a friend as Victor's ever had in the city. They have been away on shooting trips into the country. He likes and admires Victor and fully understands the pressures he's been subjected to.
'DETECTIVE ONE: He's a member of the crime car crew that is first to go to Victor's house to investigate the shooting report.
'MR. JAMES: Is the neighbour that has reported the shooting. He saw nothing, but found the body. He didn't approach it because of the blood. The type of cove you'd hope to have find you after a hit 'n run driver has hit you.
'DETECTIVE TWO: The other member of the crime car crew that is first at Victor's house.
'MOBILE VAN DRIVER:
'WIRELESS OPERATOR: A constable in the Mobile operations van.
'UNIFORMED POLICEMEN: (6)'.