Micallef appeared on the art scene in 2000, winning second prize in the BP Portrait Award competition at the National Portrait Gallery, London. Since then his mix of political imagery fused with contemporary expressionism has won him worldwide acclaim. He illustrates many contemporary cultural aspects and connects them with the human experience. Abstracted human forms delve beyond pop culture and bring to the surface many of the things that operate beneath the cultural construct.
Micallef has exhibited throughout the world in locations including Los Angeles, New York, Tokyo and Bethlehem. Recent group exhibitions include the Royal Academy's Burlington Gardens (part of the GSK Contemporary) the Tate Britain and the ICA in London.