The drawings were made in secret depicting scenes of daily life and personalities in the camps in Singapore and Thailand, working on the Death railway.

[2][4] Mennie's drawings were donated to the archive at the Imperial War Museum, but came to wider public notice when a selection from a separate source were featured on an episode of the BBC television programme Antiques Roadshow, filmed on 18 September 2011 at Manchester.

[2][3][4] Mennie described his 4-year PoW itinerary in a part of a letter to his mother written at Pratchi camp, Thailand, 5 September 1946.

Then after a 6-day voyage on a barge up the Mae Klong river from Kontonburi was dumped on the side of a mountain with jungle starting from the bank.

In May 1945 he was moved again, a 6-day journey to Pratchi camp where the prisoners had to tunnel into a mountain to make bomb proof magazines for ammunition.

Mennie created two series of secret drawings while he in the camps: His meagre materials were pen, pencil, scraps of paper and card including 'white space' torn from manuals, plus a Chinese 'Children's watercolour paintbox'.

[4] After graduation from the Westminster School of Art in circa 1931 he worked as a commercial artist in London for eight years until he enlisted in the army in 1940.