In the course of her research she learned that for nearly four years Dame Margot had, along with other women - a mixture of British, Australian and Dutch - been kept captive in a Japanese prisoner of war camp in Sumatra. So began a labour of love that swiftly took Warner bumping along deserted roads in Indonesia with another survivor, Sister Catherine, a Dutch nun. The result was an Omnibus documentary, "Women in Captivity".
"It was very exciting because I was following up lots of different leads. It was a measure of how involved I got with these women. I thought their stories were amazing, and I wanted to go on with it." A book co-authored with John Sandilands, Women Beyond the Wire, followed (now republished) and then in 1981 Warner took the idea for a drama series to the BBC. Tenko was born and for three series, despite being filmed in a disused mine near Bournemouth, vividly depicted life for the women in the camp.
The same ground, with far greater financial resources, is now being covered by Paradise Road. Warner, the only person to know the whereabouts of all the British survivors, was drafted in as a consultant.
It is hard to credit that only 20 years ago most people were supremely ignorant that these female POWs had existed.
"We had all heard about the Burma railway and male prisoners but I discovered these women who had been through hell," Warner says. "Yet they hadn't talked about it for 40 years. It was such an eye-opener. They had been completely deprived. The Japanese kept away the medical rations and stopped Red Cross supplies. Over half the women in the camp died.
"They had put the experience behind them and until I came along nobody had asked them about it. They looked just like my mum, ordinary women with perms going into the supermarket." One reason for this was apparently the attitude of the British government of the time, verified in letters that Warner was shown. "They were so ashamed that Singapore had fallen in the first place that even their relatives were told not to meet them off the boats in Liverpool. While a big fuss was made of the military men they didn't want any publicity for the fact that all these civilian women had been captured. As the women hadn't been lorded when they returned, they just wanted to forget about it too."
In many cases some considerable persuasion was required before the women would discuss their terrible memories. "They said, `Oh you won't be interested in that'. But once I went to their homes and talked to them it was as if the floodgates had opened. Some of them did break down because it was something they hadn't wanted to think about."
One of the women Warner met was Norah Chambers. At their meeting Chambers produced reams of original sheet music that she had laboriously notated while she was in the camp. It is Chambers on whom the Glenn Close character in Paradise Road has been based. In an effort to raise the spirits of the other inmates Chambers suggested the women form a vocal orchestra.
"The original music was so precious which is why Norah had kept it because it was written on scraps of paper or torn up old books. She had been determined that she would carry it out of the camp."
Already in her thirties when she was captured, Chambers had married an engineer and was living in Malaya when the Japanese overran the Malayan Peninsula. "There was a whirlwind rush to what they thought was the safe fortress' of Singapore. She had to put her daughter, Sally on a boat to Australia and she told me she didn't know whether she would ever see her again. The situation was much worse than they had been led to believe and they got caught because they were evacuated too late." Warner and Chambers struck up a deep friendship that lasted until Chambers' death five years ago. "I was very saddened - it was a real wrench for me. She came to my home and she was a special part of my life."
The inevitable question is how present day women would cope today if placed in a similar situation. Warner seems confident that they would. "I think that when you're presented with that set of circumstances you just get on with it. You have to in order to survive. Norah Chambers and the others were colonial women and they hadn't known any hardship before they were herded into these camps." Chambers she says was a particularly remarkable character. "She was a combination of somebody very warm and caring but with a very steely side to her. You could see the strength shining from her and understand why she had survived."
Often during their discussions with Warner the women mentioned others who had not been so fortunate. "Whatever resources they had they believed that survival was also due to some mental attitude. They told me they used an expression when somebody died - `She turned her face to the wall.' It meant that the women had given up in spirit."
Warner hopes that in some small way her book stands as a tribute to these women. She remains incensed however that their heroic strength has yet to be honoured in an official manner. "These civilian women are still in unmarked graves in the middle of the jungle. There's no headstone for a granddaughter to go and mourn her grandmother. There is a roll of honour in Westminster Abbey but there's no memorial to them.
"Without wanting to sound sanctimonious I feel very privileged that these women did confide in me."
`Women Beyond The Wire', Lavinia Warner and John Sandilands. Arrow books, pounds 6.99.Reuse content