Nearing up to the end of the game when your in a lava filled place after fighting two bosses in a row, at this point you have to collect the dark dragon blade and try to escape as sarah is waiting for you.

When your about the pick up the dark dragon blade as your hands are about to touch the sword keep tapping start and back a few times I don't know how it exactly works. And then the game skips to when your clinging on to Sarah and going up, it saves a little time and effort if anyone has got upto this point.