### Clue: Facet of dreadful spa using shock therapy (6)
### Answer: ASPECT 
 ### Explanation: Definition: Facet
 **Anagram of**(dreadful) SPA **plus**(using) ECT(abbrev. for "electroconvulsive therapy";shock therapy using electric currents).  It would really come as a shock if that were part of the treatment at a spa … unless it was one that masochists went to – and a dreadful spa for others.