While trying out the spy glasses, spy hat, and other items in their new spy kit, seven-year-old Henry and his dog Mudge make a new friend and form a spy club.
For Henry and his big dog Mudge, summer means going on a picnic in the park, taking a bath under the garden hose, and going to the top of the big green hill.
Annie and her pet rabbit, Snowball, invite Henry and Mudge to a dress-up birthday party, but there is some confusion about what the guests are supposed to wear.
While Henry's parents are at a Sweetheart Dance on Valentine's Day, he and his dog Mudge have a wonderful time staying at Mrs. Hopper's house, where they enjoy tea and music and dressing up in various costumes.
Follows a sleepover adventure shared by Annie and her pet bunny, Snowball, who spend a fun-filled night of baking cookies, braiding hair and telling bedtime stories at Annie's grandmother's house.
For Henry and his big dog Mudge, spring means admiring the first snow glory, playing in puddles in the rain, and watching the five new kittens next door.