In Old California is a 1942 American Western film directed by William C. McGann starring John Wayne, Binnie Barnes and Albert Dekker.

Wayne plays Tom Craig, a Boston pharmacist who relocates to Sacramento during the Gold Rush.

Boston pharmacist Tom Craig arrives in Sacramento and visits a saloon while waiting for a river boat.

The locals scoff at his eastern attire and polite manners and are astounded when he orders milk at the bar.

When Kegs McKeever comes in rampaging over his toothache (again), Tom manages to treat him to the relief of those in the bar.

On his way to the boat he carries singer Lacey Miller across a mud puddle angering her fiance Britt Dawson who hits Tom.

Britt pressures a Mr Carlin into selling part of ranch to him cheaply, eventually shooting him in the hand.

When Britt finds out he is angry until Lacey points out that she is a partner and expects to make a lot of money as it is the only drugstore in town.

Helga, Lacey's lady's maid who is cleaning the drugstore, pulls Kegs sore tooth out while he is asleep and marches him off at gunpoint to get married.

While they are out, Whitey, the town drunk, enters the store and drinks Tom’s elixir tonic.

With the growth of Sacramento due to gold seekers there is now a US Marshal in town, but he refuses to open a case against Britt as the poisoner.

Britt tells Joe that if they steal the medicine they can sell it for a huge amount at the gold fields.