Can I stop Powerpoint from ending (advancing past final slide)?

I have a Powerpoint presentation that is shown from within Powerpoint. Currently if I click the mouse or press Page Down at the last slide then the presentation ends and it goes back to PowerPoint screen. Is there a way to force it to stay on the last slide even if I click the mouse or press page down? I only want it to leave the presentation if I press Esc or some other special key. This is because I have some hidden slides after the final slide that I may want to show, and sometimes I click and the presentation ends before I remember to hit 'H' to move to the hidden slides.