The Constant Gardener seeks to juggle three film styles—the romance, the thriller, and provocative social realism. On all three levels, the film succeeds, especially with the latter.

Much credit should go to director Fernando Meirelles, who has synthesized a virtual textbook of different film techniques. The uses of set-ups, location filming, lenses, film editing, and close-ups were simply dazzling. While the panoramic scenes of the African landscape were breathtaking, there was a starkly contrasting approach to the close-ups in the scenes in the city. The jittery, hand-held camera sequences added to the dramatic tension and underscored the urgency of coming to terms with poverty and disease.

The romantic portion of the film was anchored by the two characters played by Ralph Fiennes (Justin) and Rachel Weisz (Tessa). Their first meeting was dynamically presented as Tessa was a social activist heckling Justin as he was making a political speech. When the hall was cleared, however, it was Justin who was actually comforting Tessa after her outburst. The juxtaposition of the placid, passive Justin versus the fervent, hyper-kinetic Tessa was brilliantly established in that opening scene. 

The strands of thriller and social realism are inextricably tied together in the film. As a whodunit, The Constant Gardener seeks to uncover what actually happened to Justin and Tessa on their African journey. At the same time, the main culprit that emerges is the heavy hand of greed as the pharmaceutical companies exploit helpless victims of tuberculosis for the purpose of testing and marketing an experimental drug. At one point in the film, it is disclosed to Justin that the pharmaceutical industry is no different than arms dealers.