At the age of 16 in 1993, O'Shea won the Gympie Music Muster talent competition which subsequently led to a record deal with ABC Country.
[1][2] Mark's debut album None Of The Above was released in 1996 and he won Golden Guitar Awards at the CMAA in 1996 and 1997.
[3][4] In 2002, Mark formed the rock/pop group Zinc with brother John O'Shea and Adam Ray.
[5] In 2007, Mark and wife Jay moved to Nashville, Tennessee and began performing as a duo.
In 2010, the pair began hosting their own TV show called O'Shea USA which aired on Australia’s Country Music Channel (CMC).