Period!
___________
End of story!
1 The phrases Period! and End of story! are used after giving a command or declaring how a situation is going to go, to make it clear that you DON'T WANT TO HEAR ANOTHER WORD of protest from the listener(s) or anything to the contrary. In this context, you may also hear And that's all there is to it! [stress the word to].
As Billy's driving his teenagers to school, they plan his wife's birthday dinner that evening.
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Billy: Kids, as you know, today's mommy's birthday. So I thought tonight, we could invite your uncle Ronnie over, order some sushi, do a nice cake...
Adam: Yuck! I hate sushi. Let's get pizza.
Billy: Your mother loves sushi, and it's her birthday. You don't have to eat sushi — you can order something different from the menu.
Sandy: Does uncle Ronnie have to come over? He always gets drunk and obnoxious.
Billy: He's your mother's brother, honey, of course she'll want him there.
Adam: Well, I'm going to Stuart's house then. He just got a new PlayStation.
Sandy: And I'm going to stay in my room and watch my show.
Billy: You're both going to have dinner with your mother tonight. Period! And you're not going anywhere until after the cake. End of story! Your mother's birthday only comes once a year. You're both going to be there and that's all there is to it!
Note that for these forms to sound natural, there has to have been some protest or resistance, which the speaker wants to put a stop to.
For instance, let's take that scene in Star Wars where Darth Vader makes his famous declaration to Luke Skywalker that he's actually his father:
[00:56]
Darth Vader: Obi Wan never told you what happened to your father.
Luke Skywalker: He told me enough! He told me you killed him!
Darth Vader: No. I am your father.
Here, Darth Vader's making a declaration, yes, but he's announcing that he's Luke's father FOR THE FIRST TIME, so Luke hasn't had a chance to argue. Luke doesn't believe him and he'll even argue that he's not his father, but until then, there's no reason for Darth Vader to insist. Therefore, it wouldn't make any sense for him to have started out by saying "I am your father. Period!/End of story!/And that's all there is to it!" because, again, in order for these forms to work, there has to have been some dispute, argument, disagreement, resistance, etc. that the speaker wishes to put a stop to.
For instance, in this cartoon, it's obvious that the poor boy had already complained about having to wear those garish pajamas, and his mother puts an end to his complaining by saying End of story!!! meaning that she doesn't want to hear another word. To that end, she could've also said:
...you're going to wear them. Period!!!
...you're going to wear them and that's all there is to it!!!
