"Music of the Spheres" is a mini-episode of the British science fiction television series Doctor Who that premiered at the Royal Albert Hall in London before the Intermission of the Doctor Who Prom on 27 July 2008, for which it was especially made. The Doctor Who Prom, including the audio for "Music of the Spheres", was broadcast simultaneously on BBC Radio 3. "Music of the Spheres" was shown on the official BBC Doctor Who website during the interval and the concert itself was filmed for later broadcast on BBC One on 1 January 2009.

The episode has live and pre-recorded components: the pre-recorded component takes place in the TARDIS; the live component is the Doctor Who Prom which took place during the episode's first transmission. Consequently, a major component of the episode is that it breaks the fourth wall: the Doctor (David Tennant) "converses" with the audience and conducts the orchestra to perform his symphony Ode to the Universe. He is antagonised by the Graske (Jimmy Vee), who intends to cause mischief at the Prom.

The beginning of the episode depicts the Tenth Doctor composing Ode to the Universe: a symphony based on the "music of the spheres"—an aural representation of the Universe's gravity patterns. During the composition, a Graske teleports into the TARDIS to warn the Doctor about the imminent opening of a portal linking the TARDIS to the Doctor Who Prom at the Royal Albert Hall. The Doctor conducts the orchestra in a performance before he realises the Graske has escaped into the Prom with his water pistol. He forces the Graske's return by "reversing the polarity of the neutron flow" and banishes him from the TARDIS and to the other side of the universe. At the end of the episode, he tells the viewer that the music of the spheres encompasses everyone.

...
Wikipedia