Former surgeon Dr Martin Ellingham arrives in the sleepy Cornish hamlet of Portwenn, replacing the former GP who has died.

Martin's surgery officially opens for business, but patients continue to treat it as a drop-in cafe.

When an epidemic of diarrhea strikes the village the doctor takes immediate action. This, however, does not go down well with the population.

The doctor pays a visit to the forester, who apparently shares his shack with a giant squirrel. Little Peter Cronk gets into trouble over some nest boxes.

An old friend of Aunt Joan's turns up, stirring up old memories. In the meanwhile both Doc Martin and Elaine are struggling with other people's affections.

Word is getting out in the village about the doctor's 'little problem' with blood. When Peter Cronk is hurt concern about him brings Martin and Louisa closer together.