### Clue: Old maestro taking cap off hole in device filming workers? (7)
### Answer: BEECHAM 
 ### Explanation: Definition: Old maestro
 **1st letter of**(taking cap off) "hole" **contained in**(in) [ BEE-CAM(short for "bee-camera", what one might call a device for filming bees, a caste of which are the workers) ].
Answer: Thomas, the late English conductor.