Bear doesn't go to sleep when he is put to bed, so next morning he is truly a 'bad mood bear'. He has tantrums, is rude, and is not at all nice to his friends. In the end, he is smacked and sent to his room, and after a nap, he isn't a bad mood bear any longer. The pictures are cosy (the bear family are cuddly teddies), and it is quite a realistic story about what tiredness can do to a child's personality.