[citation needed] Aitchison's earliest work was a script called Under Her Spell written for Grace Gibson Radio Productions using the pseudonym David Carrick.

The series became widely popular not just in Singapore, but also neighbouring Malaysia, Thailand, Indonesia, Hong Kong, China, and Vietnam with over three million copies sold.

In June 2009, Aitchison launched a new series called The Young Immortals, featuring the trio of Train Tang, Jeffry Hunter and Tamaryn.

Aitchison's other works include the Sarong Party Girl series (1994, 1995, 1996), The Seriously Funny Anti-Stress Book (1995), and Terror In Bali: An Eyewitness Account (2003).

In 1998, Aitchison penned the prose work Recollections, a recount of the different phases of Singaporean history read at National Day ceremonies held in schools across the island.