Need help on hacking a prop

In my after halloween sale shopping, I picked up this prop from target that is a head bust that when you press a button, it will do an evil laugh and say a short message with its eyes lighting up and mouth moving. I was wondering if there was a way to hack this prop and make it say what I want. I don't know much about hacking props like this, but I figured that since it must already be programed (it has a few different things it will say), that it might be doable. So if someone could give me some guidence or point me in the right direction it would be great!
thanks, Mike