The new version of the game has subtitles for all the cine-films. This is partly so people can play it with the sound down - but also I...I mean the professor...does have a tendency to mumble a bit sometimes.
Subtitles are off by default, but can be activated from the controls and settings menu.
You can also see how far you are through the game with the progress indicator down on the bottom right corner - it only appears once you are a little way into the game.