From the moment he was born, it was just Leonard and his mother against the world. An imaginative, friendless child, Leonard was never lonely, and even as a man in his thirties, he was content living with mother, ghost writing children's encyclopaedias and regularly playing board games with his best friend Hungry Paul. That is, until his mother suddenly dies.

Leonard faces the world with fresh eyes, aware that if he's not careful, he's going to end up living a small life of complete insignificance. But just how does he expand his world? Hungry Paul's own universe is exactly the size he wants it to be, but his mother Helen insists that he attend the local hospital with her as a volunteer visitor. Hungry Paul struggles with small talk, but after a minor upset with another patient, he sits in companionable silence with Mrs Hawthorn. Meanwhile, Leonard meets a new colleague, Shelley, an office fire warden who makes him smile for the first time in weeks.

During his shift as a casual postman, Hungry Paul delivers a letter to himself with good news. Leonard successfully asks Shelley to lunch and they spend an hour together which feels like the start of something. With a date planned for that evening, Leonard cancels his usual game night with Hungry Paul. Discombobulated, Hungry Paul goes to visit Mrs Hawthorn but on the way he discovers the chocolates his mother bought for the hospital nurses are out of date. Incensed he brings them to the local shop and demands recompense. Elsewhere, Leonard and Shelley go on a first date.