The most pervasive theme in Maurice Maeterlinck's The Blue Bird is that happiness is achievable but must be actively pursued. The children set out on a quest to find the elusive Blue Bird of Happiness, but they encounter obstacles, danger, and fear along the way. Mytyl comes to symbolize the human fears that grip everyone during the pursuit of happiness. She lacks courage and is ready to turn back and give up on the quest numerous times. However, in the end, both she and Tyltyl realize that happiness, symbolized by the blue bird, has been in their home all along; they simply have not recognized and valued it.

The children visit the Palace of Happiness, and it is there that many luxuries of life are personified. The luxuries symbolize those ideals enjoyed by few in an ironic display of happiness: The Luxury of Being Rich, The Luxury of Satisfied Vanity, The Luxury of Drinking when you are not Thirsty, The Luxury of Eating when you are not Hungry, The Luxury of Knowing Nothing, The Luxury of Understanding Nothing, etc. Such luxuries are personified as ugly and disfigured. The Luxury of Understanding Nothing is blind. The Luxury of Sleeping More than Necessary has hands made of bread crumbs and eyes made of peach jelly. The Luxury of Eating has legs made of macaroni. Light, symbolizing knowledge, warns the children:

They are very affable. . . . They will probably invite you to dinner. . . . Do not accept, do not accept anything, lest you should forget your mission.

This is a cautionary statement meant to remind readers that it is easy to fall into the luxuries of life, but those ideals are self-serving and will not lead to ultimate fulfillment.

The Palace of Night shows a conflicting image of mankind. Here, it is clear that mankind is making some progress, weakening some of the hardships of the world. When Tyltyl asks if he should be careful when examining sickness, Night responds:

They are very quiet, the poor little things. . . . They are not happy. . . . Man, for some time, has been waging such a determined war upon them! . . . Especially since the discovery of the microbes. . . . Open, you will see.

Outside the plot, the reader can understand how this is not a situation of gravity. Indeed, this is something to celebrate. However, Night justifiably is concerned about opening the door of War:

They are more terrible and powerful than ever. . . . Heaven knows what would happen if one of them escaped! . . . Fortunately, they are rather heavy and slow-moving. . . . But we must stand ready to push back the door, all of us together, while you take a rapid glance into the cavern.

And, indeed, it does take the efforts of the entire group to close this door. Thus, humanity is both making progress in treating illness and in escalating the violence of war.

The power of family is reinforced throughout the play. The brother and sister experience this magical, dreamlike world together. If it is just a dream, it is a shared dream, one they both recall upon awakening. The power of a mother's love is personified, and the children examine how much more beautiful it makes their mother as she tells them,

Do you understand, Tyltyl dear? . . . You believe yourself in Heaven; but Heaven is wherever you and I kiss each other. . . . There are not two mothers; and you have no other. . . . Every child has only one; and it is always the same one and always the most beautiful; but you have to know her and to know how to look. . . . But how did you manage to come up here and to find a road for which men have been seeking ever since they began to dwell upon the Earth?

This kind of love leads to the Great Joys: the Joy of Understanding, the Joy of Being Just, and the Joy of Seeing What Is Beautiful. Joy is differentiated from Happiness and must also be kept apart somewhat from the Light of Knowledge. The Happiness also makes an important note to Tyltyl when he asks about a particular Joy:

That is the Great Joy of Loving. . . . But, do what you will, you are ever so much too small to see her altogether.

There is therefore a certain amount of experience that is needed in life to fully appreciate some of the greater joys.

Although the play seems almost a fairy tale with simple language and a host of animated characters, from trees to animals, it conveys some deep truths about the quest for happiness that humans continually seek.

The Blue Bird, a fantasy in six acts, is intentionally cast in fairy-tale form. The play opens in the cottage of Tyl, the woodcutter. While their parents sleep, the children, Mytyl and Tyltyl, see through their window the house of their rich overlords, where an extravagant party is taking place. The children are saddened because they have been told that there is no money for Christmas at their house. Suddenly, a thin, hunchbacked woman appears. The children think that it is their poor neighbor, Berlingot, but the woman claims to be a fairy named Berylune. As proof, the fairy produces a magic diamond that allows the children to see the internal selves of objects and animals. With one magic turn, the dog and the cat assume human shape, although they each retain the facial features of their species. With another turn, the cottage begins to transform: Bread, Fire, Water, Sugar, and Light begin to speak and take on human characteristics. Each creature and object has its own inherent personality. Tylo, the dog, is filled with exuberant love and kind words for the children; Tylette, the cat, begins immediately to seek allies in a revolt against human dominance. Sugar tries to settle this conflict with sweet words. As the children are astounded by the transformations, Berylune advances her request: that Mytyl and Tyltyl undertake to find the Blue Bird of Happiness, which will aid her in making Neighbor Berlingot’s little daughter well. The children and their transformed friends set off to search for the Blue Bird.

The search occupies acts 2 through 5, with each act divided into two or more scenes. Each scene takes the children, under the guidance of Light, to different exotic locales, including the fairy’s house, the Land of Memory, the Palace of Night, the Palace of Happiness, the Graveyard, and the Kingdom of the Future. In each locale, the children seem to find the Blue Bird, but something always occurs to bring failure. In one place, a blackbird appears to turn blue, only to revert to black when it is taken from its natural habitat. In the Palace of Happiness, Tyltyl and Mytyl discover literally dozens of blue birds, but they all die as quickly as they are caught.

Other events occur at each of the locales which make for puzzling, frightening, or uplifting experiences. In the Palace of the Night, the children encounter ghosts and terrors; in the Land of Memory, they are reunited with their dead grandparents and even with their brothers and sisters who died. In the Kingdom of the Future, they meet children yet to be born.

In act 6, the children return home empty-handed on Christmas Day, only to discover that their pet turtledove has a decidedly bluish tint and that when Neighbor Berlingot’s daughter sees the turtledove, she is cured and becomes happy.

As The Blue Bird opens, Tyltyl and Mytyl are asleep on Christmas Eve. They appear to waken, but their activities are meant to represent their dreaming. The cottage door opens to admit an old and unattractive fairy, Bérylune, who resembles their neighbor, Berlingot. The fairy tells the children to find the blue bird for her little daughter, who is ill and cannot walk. She gives Tyltyl a green hat with a magic diamond on it. Turning the diamond will allow Tyltyl to see things as they really are and also to see the past and the future. When Tyltyl turns the diamond, the inside of the simple cottage gleams like the interior of a palace, and the children see magical things: Bérylune becomes beautiful; the Hours dance out from the grandfather clock; and the souls of Tylo the dog, Tylette the cat, Water, Fire, Bread, Sugar, and Milk appear, as does a beautiful lady, the soul of Light. The souls will accompany the children on their search for the blue bird; all leave through the window, which expands to become like a door, and proceed to the castle of Bérylune.

After all have donned beautiful new garments at the fairy’s castle, the treacherous cat tries to persuade the other souls to work against the children, because if they find the blue bird they will learn all there is to know and keep everything else in the world subordinate. The faithful Tylo, for whom Tyltyl is a “god,” threatens Tylette but is warned by the unsuspecting boy to leave the cat alone. The children are now very hungry, so Bread, dressed as a Turk, uses his scimitar to cut off a couple of slices of his huge stomach for them, and Sugar breaks off the delicious barley-sugar fingers of her left hand (they grow back immediately) for the children.

Before they leave to seek the blue bird, Bérylune tells the children to go to the Land of Memory to visit their grandparents. The children wonder how they can do this since Granny and Gaffer Tyl are dead. Bérylune explains that they are still alive in their grandchildren’s memories. Tyltyl and Mytyl have a joyous reunion with their grandparents and their seven dead brothers and sisters, learning that the dead always awaken and see their loved ones again anytime the living simply think of them.

After this happy experience, a series of misadventures begins as all start on the quest for the blue bird. In the Palace of Night, Tylette betrays the children, advising Night to frighten them so badly that they will not dare continue. Behind locked doors Night keeps Ghosts, Terrors, Sicknesses, and Wars, which do frighten the children; Tyltyl continues to investigate, however, and behind the last door he finds a beautiful garden containing thousands of blue birds. The children catch several and take them to Light, the strongest and most knowledgeable of their companions. All the birds die, however, and the children realize that they still have not found the blue bird that can live in daylight.

In the forest scene the children are frightened by the trees and animals: The soul of the Oak complains that his family has suffered much harm from Tyltyl’s father, who is a woodcutter, and the soul of the Sheep lists the number of his relatives that have been eaten by man. The trees and animals attack. Although Tyltyl and Tylo fight bravely, they would eventually be overwhelmed if not for the arrival of Light, who instructs Tyltyl to turn the diamond. When he does, the souls of the trees flee back inside their trunks, and the souls of the animals disappear.

The children go next to the Palace of Happiness, but here they first encounter “the dangerous Luxuries,” such as Being Rich, Satisfied Vanity, and Eating When You Are Not Hungry, who try to corrupt their visitors. Light reminds Tyltyl of the diamond, and as he turns it, the Luxuries are revealed in their true ugliness. The same palace contains the Happinesses, such as those of Spring, of the Blue Sky, and of Sunny Hours and the most beautiful ones of the home, the Happiness of Loving One’s Parents, and the Happiness of Being Well. The children then meet some of the Great Joys, such as Being Just, Seeing What Is Beautiful, and Maternal Love. Act 5 contains the famous graveyard scene, in which the children watch as the graveyard is transformed into a beautiful garden. Tyltyl, after searching, cannot find any dead in the lovely garden.

In the Kingdom of the Future, Tyltyl and Mytyl meet the children who are yet to be born. One states that he is destined to develop thirty-three remedies to prolong life; another will invent a machine that will fly; another is to bring joy to the whole world. Sadly, another child will take three diseases with him when he leaves to be born, and another says that he must remember to take with him the crimes that he is destined to commit.

At the beginning of act 6, the children return home. Their dream journey has lasted exactly a year, though in reality only a few hours of one night have passed. In the final scene, the children are shown still sleeping. Their mother awakens them and becomes very concerned about their health when they try to tell her about their journey. The neighbor, Berlingot, arrives, looking very much like Bérylune to the children. Since Berlingot’s daughter is very ill, Tyltyl decides to give her his pet dove, which seems to have miraculously turned blue. The crippled girl, who can now run and jump as normal children do, comes to thank Tyltyl. When Tyltyl tries to show her how to feed the bird, it escapes, and the young girl sobs in despair. Tyltyl tells her not to cry, that he will catch it for her again. Then he turns to the audience and asks them, if they find it, please to give it back to the children: “We need him for our happiness, later on.”

Almost all of The Blue Bird except the final scene is meant to be part of the dream shared by Tyltyl and Mytyl. Much of the interest in their dream world is created by the costuming, the varied stage effects, and the appearance of such speaking characters as Fire, Night, Oak, Sheep, Time, Maternal Love, and various children in the Land of the Future.

Because the play is a fantasy for children in which miraculous things are supposed to occur right before the eyes of Tyltyl and Mytyl, Maurice Maeterlinck thought of The Blue Bird as a play to be read rather than performed. He changed his mind when the greatest of Russian stage directors, Konstantin Stanislavsky, traveled all the way to southern France to discuss with Maeterlinck his ideas for staging the play. The playwright, delighted with Stanislavsky’s plans, gave him permission to stage the play.

Maeterlinck’s stage directions are elaborate and lengthy, frequently running for more than a full page. The extraordinary demands of the playwright and the extraordinary abilities of the original director are clear in the opening scene. As soon as Tyltyl first turns the diamond in his green hat, miracles begin. The aged fairy changes into a youthful fairy princess of astounding beauty; the walls of the house begin to shine like jewels; the face on the grandfather clock smiles and winks; and the clock door opens to allow the entrance of the Hours, a chorus of lovely ladies, who laugh gaily as they dance to beautiful music. The dog and the cat cry out as they disappear through trap doors, to be replaced by the souls of Tylo and Tylette. Also, the souls of the loaves, dressed “in crust-coloured tights . . . and all powdered with flour,” leave their bread pan and rush around the table, pursued by the soul of Fire, who laughs wildly as he threatens to brown them. Later, Light appears, dressed in long veils, transparent and dazzling.

The scene with the greatest amount of stage action for the children occurs in the Forest, when they are threatened by the trees and animals. The Bull is so angry that he has to be restrained by the Ox and Cow, who grab him by his tail. Even the old Oak, with moss on his feet, moves to attack. The devoted Tylo breaks the bonds that had been placed upon him by the Ivy and rushes to defend his little master.

The staging of the graveyard scene is most memorable. When Tyltyl turns the diamond to reveal things as they really are, the audience must first endure one “terrifying minute of silence and motionlessness”; then, however, crosses fall, graves open, tombstones rise, a marvelous light fills the stage, flowers grow, and birds sing. After this transformation, the scene has but two lines of dialogue. As the children examine the grass without finding any graves, Mytyl wonders where the dead are. The curtain falls as Tyltyl speaks the line that brought astonished gasps from early audiences: “There are no dead.”