Join the dots game

I want to create a join the dots game where an user joins specific dots together to complete a picture.
At the moment I have the complete picture and an incomplete picture with numbered dots. Each dot is an instance of the mc Dots.
I need some ideas on how to implement the game.
My basic idea is this:
The user clicks on a dot and draws a line to another dot (what draw functions has flash got that the user can use?).
It's easy enough for Flash to know which dot was under the mouse pointer when the mouse was pressed and released, so i'd like to write a function that draws a line between the dots.
OR the user can draw any old line which flash draws as they drag the mouse, with flash only noting that two dots hav been linked up.
Once all dots have been linked up correctly, then the complete picture is shown.

Any help would be greatly appreciated!
Jeek.