Andvari
Hero
What you could do is pitch a campaign the premise of which is that the characters' all had magic items that, as part of their background story have already been taken by the BBEG. This way, the players already have a partial background story and motivation to go on the adventure. They also won't be annoyed by you suddenly removing the items they spent time picking because they thought they were going to use them.
And make them pick weaker items, so that if they defeat the BBEG, they can actually recover them as a reward for completing the story arc without destroying the balance of the game. And look over the items to ensure one of them isn't an item that in retrospect could have been used to easily escape the BBEG and thus undermine the background story.
And make them pick weaker items, so that if they defeat the BBEG, they can actually recover them as a reward for completing the story arc without destroying the balance of the game. And look over the items to ensure one of them isn't an item that in retrospect could have been used to easily escape the BBEG and thus undermine the background story.