subbuteo

This is a dusky shrike the dark morph of long-tailed shrike.

Dylan

subbuteo

There is a new photo of dusky shrike here.   There is a picture of the darkest form on page 215 of the latest Birds of S China and HK. They are uncommon but certainly not hard to see thanks to their noisy habits and tendency to sit prominently; I see one regularly near home.  I think your picture is of an intermediate bird- not quite a full dusky morph.