### Clue: Shocking art movement has a following — I'm not sure about it on reflection (9)
### Answer: TRAUMATIC 
 ### Explanation: Definition: Shocking
 **Reversal of**(… movement) ART **plus**(has) [A **placed before**(following, in a down clue) UM(expression of uncertainty/"I'm not sure") ] + **reversal of**(… on reflection) [C(abbrev. for "circa"/abut when referring to years or other time periods) + IT].