[5] It received praise from critics at the time for its characterization of the people and culture of Haiti and its exploration of Vodou, although some reviewers questioned Seabrook's credibility and the accuracy of the material.

[14] The Magic Island documents William Seabrook's experiences on a trip to Haiti, during which time he immersed himself in Haitian Vodou, an African diasporic religion that developed in the country between the 16th and 19th centuries.

According to Seabrook's account, he interacted with a Vodou priestess, Maman Celie, who initiated him in rituals that involved drinking blood, the transferring of souls, and resurrection.

The book is notable for the chapter "Dead Men Working in the Cane Fields", which describes zombies (from the Haitian Creole word zonbi)—human corpses that have been reanimated through magical means, in this case to perform labor.

[26] Upon the book's release, Addie May Swan of the Davenport Daily Times wrote that Seabrook, in comparing the religious and lifestyle practices of the Haitian people and white Americans, demonstrates that "no two races are very far apart after all".

"[23] The Brooklyn Daily Eagle's George Currie wrote that The Magic Island "reeks with sacrificial blood, the odor of cadavers, the sinister breath of witchcraft, the horrendous exaltation of unholy terrors slaked in the steaming passions of human animals.

"[3] A reviewer for the New Statesman similarly concluded: "Although Mr. Seabrook has seen a great deal more than the average white man sees in the island, he has become so excited about it all that he cannot hope to be taken as an altogether credible witness.

"[6][31] She wrote: "Making Haiti and its inhabitants the stuff of legends obscures the less easily articulated facts of race and class as they play out in daily life in the postindependence Caribbean.

[...] During the occupation of Haiti by the United States, tales of cannibalism, sorcery, and zombies helped to justify the presence of the marines, and representations of Vodou have continued to have serious political consequences.

"[6] In 2005, author and art historian Christopher Green disagreed with Leiris's characterization of The Magic Island, writing: "It is important to realise that, if Leiris read Seabrook as a polemic against racism, his book can be read as preserving racist stereotypes of a savage and exotic Haiti, and as standing for attitudes that oppose the development there of a modern nation [...] in a real sense, Seabrook's The Magic Island actually reinforced racist convictions.