Passing Variables

I am trying to write a search application which will allow a database holding a text to be searched.

To search the text the user has to select the act, the scene, the character
Right this is where it gets tricky!

The acts all have different scenes and the scenes all have different characters - so rather than try and attempt a very complicated linked combo box for the act, scene and character I figured a more sensible way of doing it would be to have the user enter the act they want to search on one page. The value of this would then be passed by form to the next page (to get the scene).

Based on the act selected a dropdown box is then populated with all the scenes for that particular act. Following on from this I then want to pass the scene selected together with the act selected on the previous page to the next page which will get the character. I can get the scene value passed through to the character page but not the act value as this is now a server side variable. Basically what I want to end up with is after the user has selected the character on the third page, I want to be able to use all this information to build an SQL search statement.

In case you are wondering why I decided to do it in this way, I initially tried the linked combo box method but found that if the user doesn't click the boxes in the correct order it causes problems with updating the box contents. Doing it this way I figured I can force the user to enter the information in the correct order. Code: