Jack McDonald was born in Mexico to a Mexican mother and a Scots father (who played 11 instruments). Jack and his brother got their start playing music at the family's "McDonald Restaurant" in San Blas, Mexico. May and McDonald began performing together in the early 1970's in California, blending May's traditional Australian style with McDonald's Latin music roots. According to cyrilmay.com, McDonald "has become a guitar virtuoso, playing latin music to visiting Mexicans in local [Australian] restaurants. His incredible renditions of jazz and rock and roll are in constant demand by the tour boat trade."
The story of the duo is a somewhat odd one. Cyril May, born in Hellhole Creek, Australia, moved to Long Beach, California in the 1970's, where he met McDonald. Soon thereafter, and partly due to their collaboration, McDonald met an Australian woman named Cheryl, who would later become his wife. In 1975, the McDonalds moved to Australia, where they have lived ever since. Similarly, May continues to live in California, and the duo has done a vice-versa. They collaborate long distance, with Cyril recording his lyrics and music, and then sending it to Australia for Jack to add his musical arrangements.