### Clue: Extreme force set to work, filling hole on roof of office (7)
### Answer: GESTAPO 
 ### Explanation: Definition: Extreme force
 **Anagram of**(… to work) SET **contained in**(filling) GAP(a hole;a break in an object or between objects) **placed above**(on, in a down clue) **1st letter of**(roof of, in a down clue) "office".