While Big Bird is trying to water some flowers, he meets a big brown creature who introduces himself as Mr. Snuffleupagus. Mr. Snuffleupagus is feeling sad, so Big Bird tries to cheer him up by inviting him to help water the flowers, which he does by spraying water out of his snuffle. Big Bird runs to tell everyone about his new friend, but they are skeptical that the Snuffleupagus really exists. Big Bird brings them to where Mr. Snuffleupagus was, but he is gone. Everyone leaves telling Big Bird it was probably just his imagination, but later when Mr. Snuffleupagus returns, Big Bird announces happily that he knows that he's real. (thetvdb.com)