Johnson relocated to Melbourne, Australia, in 1951 where he was soon drawn into contemporary art circles, mixing with Leonard French, Roger Kemp, Inge King, Julius Kane, Peter Graham, Clement Meadmore and others.
He held his first solo exhibition there at the age of 30 in 1956, a selection of boldly geometric abstractions that set the art scene buzzing.
By this time he was sharing a studio with French and the pair experienced increasing friction from the Heide Circle, a rival group of figurative modernists—including Arthur Boyd, John Perceval, Charles Blackman and Robert Dickerson—who were still trying to control the Contemporary Art Society.
The latter artists eventually formed the Antipodeans Group, staging an exhibition in August 1959, initially to make a stand against Johnson, French, Kemp and a growing number of non-objectivist followers, although increasingly to express their opposition to American Abstract Expressionism, which they feared was about to overwhelm Australian art.
He remained unwaveringly committed to geometric abstraction, producing paintings that were stylistically and intellectually indebted to Russian Constructivism.