“I may be wrong. But frankly, I doubt it.” That line, or words to that effect, are a common refrain on “Murder, She Wrote.” It takes a certain amount of flinty self-confidence for a character to pull that off without sounding smug. We live in uncertain times. Hollywood is in its flop era. But when all else fails, there’s always Jessica Fletcher.

No matter my mood or what other TV offerings may be available, I find myself returning to “Murder, She Wrote” over and over again, at least once a week, spotting new details in episodes I’ve seen countless times before. It is my comfort watch, but it has also been instructive for me as a TV critic. Once you start analyzing the show’s various components, it becomes clear that too many of those elements are missing from more recent case-of-the-week procedurals. These basics were once considered standard but I suspect writers are out of practice. For the last decade or so, they’ve focused on the short seasons and serialized format of streaming endeavors. But writing 22 crackerjack stories a year? A lost art, I fear.

“Murder, She Wrote” — which celebrates its 40th anniversary on Sept. 30 — ran for 12 seasons on CBS and wouldn’t have worked half as well with another actor. Angela Lansbury built her career playing all kinds of eccentrics on stage and screen. But with “Murder, She Wrote,” she understood that wasn’t needed. Give us a personable woman with a good head on her shoulders and let compelling writing do the rest.

The premise is simple but wildly effective every time: Mystery novelist Jessica Fletcher goes about her day — whether at home writing or out traveling the world — when someone turns up dead. Suddenly her common sense and all that background research for her books comes in handy. Sometimes she has a personal connection and that’s why she’s compelled to help. Sometimes she’s just aggravated — offended, even — by incompetent police work. Either way, she’s going to get to the bottom of things. She’s dogged and not above a little subterfuge. But she always comports herself with class, no matter how lurid the circumstances.

There’s something so thrilling when you come across an old show and belatedly realize it’s good. Really good. That happens often with “Murder, She Wrote,” which people seem to discover and rediscover with a wonderful frequency. “Started ‘Murder, She Wrote’ for the first time,” said the comedian and writer Becca O’Neal recently. “Thought it was about a nosey lil’ old lady. Oh no, Miss Jessica Fletcher was an It Girl.”

Jessica is practical but cosmopolitan. Smart but approachable, and compassionate when the circumstances warrant. Infidelity and corruption do not shock; she’s too well-versed in the human condition to be naive about any of it. She never doubts her self-worth or instincts, nor does she let fame go to her head. She’s not impressed by wealth, though her own wealth must be considerable. If asked about her finances, she would probably demure and simply say she’s “comfortable.”

She always looks put together and just so but her wardrobe became noticeably more sophisticated a few seasons in, and even by today’s standards she never looks out of style thanks to the classic cut of her tailored skirt suits and pant suits. She’s surrounded by people of all ages and she makes friends easily. She’s always at work on her latest novel, with no signs of slowing down.

O’Neal is right, she really is an It Girl.

The show’s writing, though, is just as key as Lansbury’s performance.

There aren’t many shows of this type anymore, but the handful that have premiered in the years since have a sad trombone quality to them. The mysteries are poorly constructed, the writing hacky and immature. Audiences watch anyway because we are desperate for the pleasures offered by this genre, but these efforts are too often a simulacrum of better shows that came before. It’s not like “Murder, She Wrote” was trying to be anything other than easy viewing, but it was written with real intelligence, complexity and wit.

Jessica is as steady as they come, but occasionally the writers carve out room for Lansbury to show a broader range of her talents, whether she is playing Jessica’s daffier British cousin, the music hall singer Emma (a character who shows up only twice in the show’s entire run, but makes such an indelible impact), or briefly posing as a barfly in order to get information out of a sports bookie. She’s funny — I think sometimes people forget that – and those moments reveal Lansbury’s looser side. But she was a brilliant actress when it came to drama, as well. In one episode, Jessica has to contend with the possibility that her late husband had an affair and fathered a child while serving overseas. Her pain is very quiet and very nuanced, but she is shaken to the core.

That’s a rarity, because otherwise she’s rarely off her game. We never know the character’s age, but Lansbury was in her 60s for most of the show’s run, and Jessica is undaunted by anxieties related to technology. After spending years writing her books on a manual typewriter at her kitchen table, by the early ’90s she buys a desktop computer and the episode uses this premise as the basis for a murder mystery. In another episode, a company has contracted with her to write a virtual reality video game. When her best friend, local doctor Seth Hazlitt, scoffs at the idea, she tells him to get with it — the 21st century is around the corner! In another episode, she’s on a plane, tapping away on a laptop computer.

The show’s format can plop Jessica down anywhere, allowing for varied locations and scenarios, whether she’s on an archeological dig in the Southwest or visiting a Ben & Jerry’s-esque ice cream company in middle America, or traveling in Russia promoting the latest translation of her books. The show is not trapped by its setting, but follows a wanderlust that allows it to take on just about any kind of premise and be assured that Jessica would fit in somehow./Tribune News Service