Holly's parents promised that she could have a puppy when her new brother is born—and Holly can't decide which is more exciting: baby Adam or Rusty the terrier arriving in her home! Rusty takes to his new life like a duck to water. Literally, he loves jumping in the garden pond and even the bathtub.
The family decide to go on holiday to the Isle of Wight, and Rusty is coming too. The first few days are full of sunbathing, playing on the beach, and lots of ice cream, but when Holly gets caught in a strong sea current, Rusty has to perform his best doggie paddle to rescue her!