The film's screening at Cannes met with critical acclaim, prompting speculation it could be awarded the Palme d'Or. The award eventually went to "Entre les murs" ("The Class"). Straczynski claimed that "Changeling"s loss by two votes was due to the judges' not believing the story was based on fact. He said they did not believe the police would treat someone as they had Collins. The loss led to Universal's request that Straczynski annotate the script with sources. Although the positive critical notices from Cannes generated speculation that the film would be a serious contender at the 2009 Academy Awards, the North American theatrical release met with a more mixed response. , the film holds a 62% approval rating on review aggregator Rotten Tomatoes, based on 209 critical reviews, with an average rating of 6.3/10. The website's critical consensus states, "Beautifully shot and well-acted, "Changeling" is a compelling story that unfortunately gives in to convention too often." Metacritic, which assigns a weighted average rating to reviews from mainstream critics, reported a score of 63 out of 100 based on 38 reviews, indicating "generally favorable reviews". The film's reception in several European countries was more favorable, and in the United Kingdom 83% of critics listed by Rotten Tomatoes gave "Changeling" a positive review.