The series dealt with the experiences of British, Australian and Dutch women who were captured after the Fall of Singapore in February 1942, after the Japanese invasion, and held in a fictional Japanese internment camp on a Japanese-occupied island in the Dutch East Indies in modern day Indonesia between Singapore and Australia (the actual location of the island is not revealed in the series but it is assumed that the fictitious locations are set in south east Sumatra).

Having been separated from their husbands, herded into makeshift holding camps and largely forgotten by the British War Office, the women had to learn to cope with appalling living conditions, malnutrition, disease, sexual violence and death.

Tenko was created by Lavinia Warner after she had conducted research into the internment of nursing corps officer Margot Turner (1910–1993) for an edition of television programme This Is Your Life and was convinced of the dramatic potential of the stories of women prisoners of the Japanese.

Only Ann Bell, Stephanie Cole and Claire Oberman appeared in all thirty episodes plus the reunion.

The first series depicts the events leading up to the fall of Singapore to the invading Japanese forces in 1942, and the abortive evacuation of civilians from the city.

The second series continues with the women marching through the jungle and being split up before they arrive at a new camp, an old mission school, on New Year's Day 1943.

Tensions arise as the internees are forced to adhere to the new regime implemented by the strict and fierce official interpreter, Miss Hasan.

After a joyous reunion with old friend, Lillian, Marion is forced to take a back seat as the women's official leader in favour of the overbearing wolf in sheep's clothing, Verna Johnson.

Dorothy continues to trade favours with the guards, teaching English to Shinya in exchange for cigarettes and later discovers that she is pregnant.