this one took me ages to figure out cuz in the video he has his guitar dropped down a 1/2 step..


it goes

Bm7        A                           C#m7 
Trouble comes knocking I'll be ready alright 
       Bm7                  Bm7
with my fists up ready to fight
                           A       E     D
But i ain't gotta put my fists up everytime


the Bm7 is hammered on from a barred 2nd fret..

the E is played open and the D is played barred...


just repeat that riff throughout..