Question to people who work at banks

I have recently played the lottery and one day when I was in the bank I raised the hypothetical scenariou of winning the lottery. In other words could I win a large sum of money come in the bank the next day and deposit it like any other check. They said that it would not be possible I would have to if I were to win make an new different account. Now here is the thing. There is one part in a movie where this woman gets a million dollars wired to her account. Was this part unrealistic? I mean could someone litterally wire a million in to my account without the bank getting involved or wanting to change the account in some way?