Burkholder | Playing May 22, 4 p.m. at Lincoln Square Cinemas. 81 minutes.

In screenwriting there’s an unofficial rule that it’s unwise to write dialogue how people actually talk. Everyday speech is too oblique, too meandering. It lacks punch.

But in “Burkholder,” the latest old age comedy from Bainbridge Island director Taylor Guterson, wandering tongues are the source of humor. The characters may rarely talk in a straight line, but the side roads and alleys they walk betray unexpected charms and gems.

In fact, this meandering may be the only well of pure humor found here — this is a heartbreaking film about a man’s stubborn struggle against dementia and his landlord’s personal dilemma about how to proceed with his end-of-life care.

Principal actors Bob Burkholder and Britton Crosley portray a friendship that is as sweetly intimate as it is petty, bickering and manipulative.