Though Oliver Parker made an adaptation of the highly acclaimed comedy The Importance of Being Earnest of Oscar Wilde, however the film remains, for the most part very much faithful to its source. Truly speaking, there have been some changes in The Importance of Being Earnest but of the changes were made out of necessity and also in order to make the film-version a reasonable length for modern cinema. A direct script-to-screen adaptation would probably be somewhat short, however. In order to accomplish an appropriate running time, Parker took some scenes and spread them out over different locations. For instance, in The Importance of Being Earnest at the initial level the two protagonists Jack and Algernon do not meet in Jack's apartments but they encounter each other only at a nightclub. However, most of the dialogue remains intact in The Importance of Being Earnest, which includes the discussions of the cigarette case, Bunburying, and also of Jack's business proposal. But at the same time it should be accepted that the film's setting is strikingly different, and the scene appears to be shorter, keeping the audience in suspense so as to determine the identity of Bunburying. An explanation follows the next day at Algernon's residence, so that the remainder of the scene on film looks much more like that of the script. Parker modifies setting again as Lady Bracknell tells Jack to stop by her house the next day; it must have seemed more appropriate to the screenwriter that the "interrogation" scene should take place there instead of at Algernon's apartment. Again, as afar as the characterization is concerned, the characters in the film are almost in the original version of the comedy of Oscar Wilde, nevertheless there are minor exceptions. For instance, Jack in the movie indicates that he is 35 years of age, whereas in the original version it is 29. May be this alteration ahs been done by Parker because 35 is closer to the actual age of Colin Firth, the actor who is in the role of Jack, in The Importance of Being Earnest. It has also been learnt that Firth is quite perfect in the role, and performing at his best, in the role of a charming but quirky Englishman. In addition, since Jack is not as crafty as Algernon, Firth's bumbling nature pays off. Rupert Everett in the role of Algernon makes a good presentation, although it would have been fascinating to perceive Hugh Grant play the role, so he and Firth could reprise their relationship from the two "Brigit Jones" films. Judy Dench, seen elsewhere as James Bond's steely bureau chief, is also perfectly cast in Parker's adaptation, although her delivery of Lady Bracknell's signature line "A handbag?" leaves something to be desired after one has seen and heard Dame Edith Evans's do it in such a masterful fashion in the earlier film version.

Again, the movie also introduced scenes that were completely absent in the final draft of Wilde's script. For instance, there is no mention in the original play regarding the drinking of champagne by the servants of Algernon but in a definite mood shows the servants drinking and playing music while Algernon is absent. Furthermore, the scene in the film that involves the bill-collector's coming to deliver Ernest's unpaid dinner bills, although written by Wilde, was cut out of the original staging of the play at the urging of Wilde's director. However, by bringing back "The Gribsby Episode," Oliver Parker has made his adaptation somewhat more faithful to Wilde's original conception than the play script itself.