The original Curse of Strahd has an introduction for level 1 to 3 players called Death House. Personally I do not think this is suitable for an introduction, there are many ways for a total party kill and it can be a little boring for them.
Great adventure movies start with a fast pasted action focused scene, to grip the viewers to their seats. In this chapter of 'Curse of Strahd: Rebitten we are going to do the same and really hook our players into a long campaign.
Your parties will use a level 10 character sheets, as their characters are dropping straight into battle against the evil Count Strahd Von Zarovich. Please see my mini-supplimentals 'Improved Session Zero' or 'Improved Character Creation'.
Using the original Curse of Strahd module, I have seen some players take two sessions just to get to the death house, another four weeks inside it and maybe another four before they even meet Strahd, never mind fight him. Some people find this method and the lack of what low level characters can do, very boring. This version is designed to ramp up that excitement from the start and also give the players a reason to want to continue.
- from the publisher's blurb