Provide the theme summaries for the following conversation: 

#Person1#: Isn't there anyone at home? 
#Person2#: I'll knock again, Helen. Everything's very quiet. I'm sure there's no one at home. 
#Person1#: But that's impossible. Karen and Tom invited us to lunch. Look through the window. Can you see anything? 
#Person2#: Nothing at all. 
#Person1#: Let's try the back door. 
#Person2#: Look! Everyone's in the garden. 
#Person1#: Hello, Helen. Hello, Jim. 
#Person3#: Everybody wants to have lunch in the garden. It's nice and warm out here. 
#Person4#: Come and have something to drink. 
#Person2#: Thanks, Karen. May I have a glass of bear please? 
#Person4#: Beer? There's none left. You can have some lemonade. 
#Person2#: Lemonade! 
#Person3#: Don't believe her, Jim. She's only joking. Have some beer! 

Summary: 
Helen and Jim are invited to lunch at Karen and Tom's home. Nobody answers the door until they finally catch everyone in the garden.