James MacPherson (Roger Rees) James McPherson was once a Warehouse agent and partner to current special agent in charge of the Warehouse 13 Artie Nielsen.McPherson and Artie have a contentious past that resulted in McPherson being jailed. He is nearly equal to Artie in his knowledge of the Warehouse and its artifacts. He is charming, cunning, and brilliant and is bent on revenge against his former partner, becoming a constant thorn in his side.