McNie was given just one day to prepare, pack and say goodbye to her family before ferrying to Wellington to meet with the rest of the nurses and set sail for Apia.

The ships made stops in Nouméa, New Caledonia then Suva, Fiji before arriving at their destination, Apia, Samoa.

The heat posed the biggest barrier as McNie noted her experiences in Samoa:[7]We are very happy in our little Hospital just busy enough to keep us healthy and cheerful.

We never tire of exploring the roads and bush and finding fresh beauties ever day.McNie worked at the Apia hospital for nine months before returning home to New Zealand on the SS Atua in May, 1915.

[8][9][10] Later during WWI McNie was selected in a contingent of nurses that worked as a theatre-sisters on New Zealand hospital ships headed for the front.

[11] These ships hosted cramped living conditions and nurses, like McNie, often worked long hours from 6:30am till midnight.

[4] The SS Maheno made six trips from Anzac Cove to the Greek Island of Lemnos where the military hospitals were located.

[4][16]On 4 February 1920 McNie married Henry Meredith Buchanan, a doctor originally from Edinburgh, who was the Auckland Mental Hospital Medical Superintendent from 1929 to his retirement in 1952.