### Clue: Would-be ringmaster's energy upsetting Scottish island (6)
### Answer: GOLLUM 
 ### Explanation: Definition: Would-be ringmaster
**GO** ("energy") *upsetting* **<=MULL** ("Scottish island") 
*In *The Lord of the Rings*, Gollum is a Stoor Hobbit, corrupted by the One Ring ("his precious")