Mozart's Requiem in D minor (K. 626, 1791) is his final and unfinished composition, left incomplete at his death and later completed by his student Franz Xaver Süssmayr. This first part encompasses the Introit, Kyrie, Dies Irae, Tuba Mirum, Confutatis, and Lacrimosa, movements that have become some of the most iconic in the choral repertoire.

This orchestrated medley, originally compiled by Grant Woolard for YouTube and later arranged for full symphony orchestra by Tom Romain, weaves together famous themes from Mozart, Beethoven, Tchaikovsky, Chopin, and other classical masters. It became a viral hit online for its inventive juxtaposition of beloved classical works.

The "Ode to Joy" is the choral finale of Beethoven's Symphony No. 9 in D minor, Op. 125, premiered in 1824 – a monumental work that pioneered the use of vocal soloists and choir in a symphony. This orchestral arrangement by Tommy Thomson adapts the iconic theme for full ensemble.