The push-pull of relationships has always been at the heart of films written and directed by James L. Brooks. He’s never been a particularly visual artist, preferring to allow his words and characters to carry the weight of the drama and deliver the comic relief of his neurotic humor. From “Terms of Endearment” through “Broadcast News” through “I’ll Do Anything” through “As Good As It Gets” through “Spanglish,” Brooks has also benefited from being able to work with world-class actors who can deliver his lines as though they were their own.

“How Do You Know” is another glamorous character study that sprawls across the screen in epic detail, following business executive George (Paul Rudd) and softball player Lisa (Reese Witherspoon) as they navigate big changes in their lives. George is served with a lawsuit alleging wire fraud and is promptly bounced from his post as Chief Executive Officer at the company founded by his father Charles (Jack Nicholson). Lisa is cut from the U.S. National Softball team and falls into a romance with professional baseball player Matty (Owen Wilson).

They’ve been cut loose from their respective moors and set adrift at sea. George must deal with the added indignity of getting dumped by his career-minded girlfriend Terry (Shelley Conn) and being forced to sell his apartment.

After a couple of unpromising phone calls, George and Lisa meet on an awkward blind date on a day that both have received the worst possible news of their 30-something lives. The only way to deal with it is to remain silent, in Lisa’s estimation, and so they eat in silence and part in silence. Lisa then falls deeper into an unequal relationship with the dim and insensitive but lovable and wealthy Matty — she’s far too bright for him — while George avoids his grouchy father and occasionally receives visits and encouragement from Annie (Kathryn Hahn), his pregnant and loyal secretary.

George nurses a crush on Lisa as she tries to work through her differences with Matty. Eventually, George talks with his father and discovers that he must make a decision that will affect them both on a profound level.

Like George and Lisa, the film is bright and sunny and cheerful. It’s shot, mostly in glamorous extreme close-ups, by Janusz Kaminski, making Rudd and Witherspoon look like 40s movie stars adorned in soft-glow Technicolor. The atmosphere feels unreal, awash in luxury; despite losing their jobs, neither George nor Lisa appear hurting for money, and their supposedly modest accommodations still place them in the comfortable middle class.

Matty, who we’re told earns $14 million per year, lives lavishly in the same high-rise as George’s father. The building is located somewhere in Manhattan, we suppose, but it’s difficult to place because the locations all look like sets in a studio. We’re never sure exactly how George and Lisa are spending their time; they seem to be wandering around in a daze, coming alive fully only when they’re in the company of one another.

While all the characters are likable, the two leads seem ill-formed. George is a good-hearted fellow, but it’s not clear how he ever managed to run his father’s company for any length of time. Between the page and Paul Rudd, we end up with a very funny man, given to harmless pratfalls and charming sincerity, a feckless sort who doesn’t belong in the executive offices of a corporation. He immediately realizes that, as CEO, he will be held accountable for any illegal activities of his employees, even if he wasn’t aware of them, but beyond making that statement he doesn’t take any action to clear his name — except meet once with a high-powered attorney, who informs George of his exorbitant fee, prompting George to sell his place and move somewhere more modest.

In contrast, Lisa has a plan of action in mind for her post-playing days, but she knows she’s taking the easy way out by settling for an unchallenging relationship with Matty. Her life has been filled with pep talks and self-help messages — she’s constantly quoting platitudes, and her mirror is surrounded by Post-It notes with positive messages — yet it lacks verisimilitude. She floats along without knowing what she really wants out of life, now that her softball career is over.

Neither character ever gets really angry, a defining personality trait of some of Brooks’ best characters in the past. Even Charles, the most ill-tempered, is constantly catching himself before erupting. The reason given is that George “doesn’t hear” his father once he starts shouting, but it seems a waste to have Jack Nicholson in the role without allowing him to blow him top. George and Lisa are mild people with good self-control, and they are certainly pleasant company, yet not terribly distinctive.

“How Do You Know” is a fine way to spend two hours, filled with clever, diverting conversations and funny scenes that could only have come from James L. Brooks. If it falls short of what it might have been, it’s still a pleasure to watch.