The Symphony No. 10 of Gustav Mahler was his last, and he was unable to finish it before his death. The symphony was a highly personal work; Mahler scribbled the words "Almschi, to live for you! To die for you!", a message to his wife Alma, on the pages of the Finale. As he wrote what is there in his handwriting, he thought he was going to lose the love of his life, his wife, who was flirting her way into a mad love affair with the futuristic architect, Walter Gropius.

But fate got to Gustav first. At a mere 51 years, he contracted a bacterial infection that took him suddenly. Mahler left the symphony in five movements, the first complete, but the other four with the notes written in short score on four staves, sometimes with only sketchy indications of what orchestral instrument would play which notes.

Mahler enthusiast Jack Diether tried in the 1940s to enlist renowned composers to complete the Symphony. Benjamin Britten, Arnold Schoenberg and Dmitri Shostakovich were approached, but they refused Diether's request.

Deryck Cooke chose to orchestrate and complete the symphony, calling his work a "performing version". This version is controversial, and many conductorss have refused to perform it.

Nevertheless, the spirited conductor Simon Rattle made a few adjustments to Deryck Cooke's reconstruction and recorded all five movements. The fifth movement, the Finale, illustrates the intense drama of death and provides Simon Rattle, who once played percussion, with another chance to over-dramatize what the percussion section can do. The movement begins with the sounds of a small military band passing in a funeral procession beneath the listener's fifth-story window. From the distance, the climbing tune in the tuba comes to the listener's ear. After a few notes, the tuba's tune is stopped, smashed, blasted by the drummer slamming the deep drum as hard as he can. After a long silence, the tuba tries again, slowly rising with a tune. And, after a few notes, the ear-splitting shot from the deep drum again stops the tune. The repeated shots on the deep drum are about 10 seconds apart and relentless. And each time, the tuba and the rest of the military band try again to raise a tune, until, in time, the military band and the relentless drum pass into the distance on the streeet below, leaving the rage and reconciliation of the full orchestra to fantasize on what the Final End will be like.

At about the same time Cooke started his version, Clinton Carpenter also started working on a version of his own, which he called a "completion". Carpenter reviewed the other Mahler Symphonies to guide him in his effort, but a lot of the details he adds to the Mahler Tenth almost sound as if he's composing his own Symphony on top of Mahler's.

Joe Wheeler and Remo Mazzetti Jr. have also written completions of the Tenth, and all these have been recorded at least once.

Samples from each of the five movements