The game has three parts:
Shanghai 10-15 - Three darts on each number
Doubles 1-20+BULL - One dart on each
Shanghai 15-20 - Three darts on each number
If you hit Shanghai (1 single + 1 double + 1 treble) you get a Bonus of 100 points.
On the doubles round you get 50 points for each double and a bonus of 50 points for BULL
Check out the video with instructions by Chris Mason »