From the New York Times:
Paul Muni's portrayal of Zola is, without doubt, the best thing he has done. Fiery, bitter, compassionate as the young novelist; settled, complacent, content to rest from the wars in his later years; then forced into the struggle again, although he resisted it, when the Dreyfus cause whispered to his conscience—Mr. Muni has given us a human and well-rounded portrait.Empire Online concludes, "Perhaps not a completely reliable historical document this is however a moving evocation of an era and a heroic deed." Rotten Tomatoes has a critics score of 75%. It's listed in the book 1.001 Movies You Must See Before You Die.