Audition is a more than capable sound editor. PPro2 is a more than capable video editor. However, neither will produce a great film from bad source soyour time and money is best put into those. Ppro2 and Audition together will cost you nearly £1000 UKP I expect. If you are running to this then you should consider the Production studio and get all the other s/w too.

However, you'll also find Premier Elements is also a more than capable video editor and only costs £50 UKP. It has it's limitation but will likely do the job for you.

If quality is what youare after then your hardware is the really the limiting factor. You'll need a good camera and a good microphone for this.

Also, consider buying some CDs of sound effects for your knocking on the door and/or footsteps. You can get them cheap enough and the sound recording quality is likely as not more than equal to whaty you or I will be able to record.

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