Director Leo McCarey combined two of his favorite themes -- Catholicism and anti-Communism -- in Satan Never Sleeps, but what could have been an incisive and thoughtful commentary turns out to be overlong, oversimplified, and often ridiculous. The screenplay is certainly a primary culprit, being more interested in potboiler melodramatics than in believable dramatics, in stereotyped characters rather than living and breathing human beings. But McCarey's insistence on trying to add a layer of light Going My Way-style "church charm" over too much of the proceedings works against the heavy-going melodramatic flourishes at the story's core. Understandably, McCarey didn't have the option of shooting in China, but the locations chosen to substitute are poor, and the matte shots involving those locations are often inexcusably hokey. Fortunately, Satan does have the benefit of a talented cast that works very hard to make the film work. Clifton Webb is not ideally cast as a priest; his sophistication works against him, but his talent overcomes this obstacle. William Holden's innate appreciation of sensuality also is problematic; the script pays lip service to it, but never really comes to terms with it. Holden's sheer star power more than makes up for this problem, however. Weaver Lee and France Nuyen do very well with poorly written parts, and the supporting cast is generally fine. Overall, Satan Never Sleeps is unsatisfactory, but the cast keeps it afloat.