One of Ray Bradbury's most successful stories of his early career is "The Small Assassin". First published in 1946, it has been anthologised countless times, and appears in no less than five of his own short story collections. It has also been imitated and ripped off in several feature films and made-for-tv movies.
As far as official adaptations go, however, there seem to have only been two so far. The first was for Bradbury's own TV series in 1988. In this version, which Bradbury scripted himself, there were a few changes from the original story, but a strong central performance from Cyril Cusack as Dr Jeffers. My review of the episode can be read here.
The second adaptation is the more "faithful" version directed by Chris Charles in 2006. It is interesting to compare the two attempts to bring Bradbury's story to the screen. There are a lot of challenges. Should the film-maker show the baby as evil, or leave it to be judged from the responses of the parents? (Bradbury's own adaptation show's us the baby's point-of-view, which tips us off that something is up; Charles' version has an innocent child throughout) How to handle the complex shifts of viewpoint that the short story uses? (Bradbury re-writes, casting Jeffers as the strong central thread, condensing the parents' deaths into a single event; Charles follows the original text, passing the focus of the story from one character to the next).
Although I posted a page for the Chris Charles version of The Small Assassin over a year ago, I have only now got round to writing a review - click here to read it.