Arlecchino, oder Die Fenster (Harlequin, or The Windows, BV 270) is a one-act opera with spoken dialog by Ferruccio Busoni, with a libretto in German, composed in 1913.

It is a number opera written in neo-classical style and includes ironic allusions to operatic conventions and situations typical of the late 18th and early 19th centuries.

The composer has said that Arlecchino "has a tendency to ambiguity and hyperbole in order to place the listener momentarily in a position of slight doubt.

Larry Sitsky describes the music as "tightly integrated" and "largely based on the 'row' [of tones] which appears as a fanfare at the commencement of the opera.

"[12] And Henry Cowell has characterised this composition as "the only opera to betray knowledge of Schoenberg's early style before Wozzeck.

"[13] Because Arlecchino was too short in duration for a full evening's entertainment, Busoni composed his two-act opera Turandot to serve as an accompanying work.

[17] Prologue: Arlecchino, in mask and motley costume, appears in front of the curtain to the sound of a fanfare and delivers a brief speech about the ensuing action.

The door to Matteo's house is front left; the entrance and sign of a wine pub are further along the street, upper right.

He becomes more animated and begins to read aloud in Italian the story of the illicit love of Paolo and Francesca from the Fifth Canto of Dante's Inferno.

Finishing with Annunziata, Arlecchino leaps from the window, landing in front of Matteo, and recites the next line from Dante: Quel giorno più non vi leggemmo avanti ("We read no more that day").

[18] Grabbing the tailor's scissors to hoist his coat as a banner, Arlecchino filches the house key from a pocket, and hustling Matteo inside, locks the door.

To a series of outrageous pronouncements, the orchestra provides an accompaniment consisting of a set of variations on a pleasing Mozartian theme.

Abbate Conspicuo, noticing they are in front of the lovely Annunziata's house, which is however all locked up, calls out several times to Matteo but receives no response.

Feeling reassured, Matteo reveals the sinister news of war and the imminent arrival of the barbarians.

In the company of two constables (Italian: sbirros) Arlecchino returns in military attire and informs Matteo he has been called up and has three minutes in which to get his house in order.

The dumbfounded tailor appears in a ridiculous improvised uniform, requests and receives permission to carry along his beloved Dante, and sadly goes off, accompanied by the two constables.

In 1499 the French captured Milan and imprisoned the leader of the city, Ludovico Sforza (who was also a close friend of Leonardo da Vinci).

In response Arlecchino delivers a short speech concerning his views on marriage and fidelity: Die Treue, Madame, ist ein Laster, das meiner Ehrsamkeit nicht ansteht.

Singing in alternating 3/4 and 2/4, she attempts to flatter Arlecchino, describing how other women envy her position as his wife.

Colombina resumes her role as the abandoned woman, and Leandro launches into a classic Italian vengeance aria (Contro l'empio traditore la vendetta compierò - "Against the impious traitor shall I exact revenge").

Colombina, however, is skeptical and poses as Elsa of Brabant (Könnt' ich jemals einem Manne noch trauen!

The orchestra accompanies with a Wagnerian parody: string tremolandi, dense woodwind chords, and pointless fanfare rhythms.

According to Beaumont, the stretta's "prototype lies somewhere between Cimarosa, Mozart, or Rossini but its harmonic language, with abrupt changes of key and symmetrical chromaticisms, is pure Busoni.

As Abbate calls for prayer, Leandro revives and joins in making a quartet and a parody suggestive of Rigoletto.

[21] Finally, as they load Leandro on the cart and the sad little group leaves the stage heading for the hospital, Arlecchino appears at the attic window of Matteo's house and bids them adieu.

In procession the other characters, Leandro and Colombina, Dottore and Abbate, the donkey and the cart, the two constables, and finally Arlecchino and Annunziata, cross the stage and bow to the audience.