For Sue-Ellen Kusher, nee Doherty, growing up in the suburbs of Brisbane was far from normal. Both her parents worked for the Australian Secret Intelligence Organisation, ASIO, and in the early days of their marriage, they brought up their three children to be part of the family business. It was the 1950s during the Cold War, and Russian and Chinese communists were regarded as enemies. Sue-Ellen and her siblings would collect information about anyone suspicious - tracking number plates and going to political rallies. And most importantly of all, they learnt to keep secrets and never ask questions. Then when she was 17 her father Dudley, who she idolised, died very suddenly. At least, that's what she was told. He was a man who'd often disappeared on missions - and she was to spend many years waiting for him to return and wondering whether her mother was keeping from her the biggest secret of all.

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Picture: The Doherty family during the 1956 Olympics with Russian defectors Vladimir and Evdokia Petrov (L-R Vladimir Petrov, Joan Doherty, Mark Doherty, Evdokia Petrov, Sue-Ellen Doherty and an unidentified ASIO Officer)
Credit: Sue-Ellen Kusher