<P> When they return home they find that all the people are missing and their pets and livestock are dead or dying . They come to realise that Australia has been invaded and their family and friends have been taken prisoner . Avoiding capture by enemy soldiers, as well as retrieving Robyn and Lee who were stuck in the town and picking up one of their school friends Chris, the group return to Hell . After short period of recovery they start making plans to fight back . </P> <P> Over the course of the first three books in the series, the group succeeds in destroying a bridge that leads into Wirrawee, an enemy convoy, several houses that are being used by the enemy as a center of operations, and a nearby strategic harbour . After the harbour raid, the surviving members of the group are eventually captured and placed in a maximum security prison in Stratton . During an air - raid by the Royal New Zealand Air Force the group escapes but loses yet another member while doing so . They encounter a downed RNZAF pilot and arrange to be evacuated to New Zealand . </P> <P> Book four, Darkness, Be My Friend, takes place several months later . The group is trying to live a normal life in New Zealand with other refugees, but are haunted by their memories of the war (which is still ongoing). They are approached by the New Zealand Defence Force, who are seeking Australian guerrillas to act as guides for saboteur units that are being dropped into occupied Australian territory . The group returns to Wirrawee, their hometown, accompanied by a platoon of New Zealand troops . However the New Zealanders go missing while on a mission to destroy Wirrawee Airfield (which is being used as a major military airbase). Alone behind enemy lines once more, the group decides to attack the Airfield themselves but a combination of poor planning and bad luck causes them to fail . They return, depressed, to Hell . </P> <P> Soon after, through sheer luck, the group find themselves perfectly positioned to attempt another attack on the Airfield . This time they succeed and manage to destroy a majority of planes on the airfield . After the attack, the group find their way to the nearby city of Stratton . There they encounter a tribe of feral (and hostile) children, who have been living on the streets and hiding from enemy troops since the war began . The group rescue five of the children who have been captured by an enemy patrol and escape back to Hell . For a time the group looks after the children . During this time strained relationships are mended and the soul - destroying effects of the war are tempered by a chance to do something positive . However, this period does not last . A patrol ambushes the group near their base and after defeating their attackers in a prolonged firefight the group realises that they are no longer safe in Hell and make contact with New Zealand immediately . </P>

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