As part of the global circulation of capital and labor in the early twentieth century, labor and left activists traveled throughout the Pacific Rim. Highlighting the biographical and political journeys of two important left labor agitators of the period, Patrick Hickey and J. B. King, this essay considers the role of the agitator and the meaning of the left for the mobilization of working people during the first three decades of the twentieth century. Hickey and King both had early experiences with radical unions in North America, Hickey with the Western Federation of Miners in Utah and King with the Industrial Workers of the World in British Columbia. Their paths intersected in the formation of the left Federation of Labour (the “Red Feds”) in New Zealand. Both went on to play significant roles in Australian left labor circles in the years before, during, and after the First World War. Diverging over strategy and tactics during this time, Hickey became involved with the Labor Party of Australia and King eventually joined the Communist Party of Australia. Their biographical and political journeys reveal significant insights into the splits within the left and the public role of left labor agitators in the Pacific Rim during this period.