Mr. Hooper has to go pick up a suit at the cleaners, and needs someone to lock the door for him. Big Bird offers to do it. Mr. Hooper is reluctant at first, but he finally agrees to let Big Bird lock up the store.
Big Bird has locked the store, but forgot to turn off the lights. He manages to reenter the store but ends up "locked inside". He's confident that he'll figure everything out.
Big Bird refuses Gordon's help to get him out. Gordon tells him that sometimes letting someone help is a smart thing to do. That's how one learns many things. Big Bird agrees to accept his help.
Ernie and Bert: Ernie wants to have some cookies. Bert asks Ernie if he knows what "before" means, and Ernie demonstrates by saying that before he can have a cookie, he has to open the lid to a cookie jar, and after he closes the lid, he eats the cookie. He demonstrates a few times, until he loses his appetite for dinner. (First: Episode 0007)