The wacky-rigged Senko worm operates as a hack to bass ecology, a virus in the network, a glitch in the matrix. They’re mesmerized by it. If you ever get a chance to land one near a visible bass without spooking it, you’ll see what I mean. They just can’t help themselves but to go have a look. And then often, aw, hell, gotta try a bite.

Craziest thing is: it doesn’t look like anything in nature. Leeches don’t flex at the middle and scoot sideways. Frankly, Senkos looks dumb as hell, even worse hooked through the middle. Maybe that’s the trick—it’s stranger than fiction.

As potent as a wacky-rigged Senko might be, however, it’s strangely not that much fun to fish. Cast. Stretch your back. Slurp your water. Wait. Twitch… Repeat. It’s the fishing equivalent of watching paint dry. Those long pauses invariably fill with desirous thoughts of popping a frog or burning a crankbait. Every retrieve that doesn’t get bit takes an eternity. But the ones that do make it worth the wait. During that slow, “do-nothing” presentation, the Senko is working its magic, twitching and quivering ever so slightly when you lift it, then falling perfectly horizontally when you stop. It’s engineered to drop not too slow and not too fast, wobbling and wagging gently on the descent. And that precision engineering started with humble beginnings.

A Slug is Born
According to Bassmaster, fishing icon Gary Yamamoto made the first Senko mold from the Bic pen he was using to draw designs on a whiteboard in 1996. The writing instrument in his hand sparked a stroke of brilliance.

“I originally wanted to make a twitch bait like the Slug-Go,” Yamamoto told Bassmaster, “but after the initial phase of testing it turned out that the Senko was better as a finesse bait.”

It wasn’t a completely new idea. The Slug-Go came out in the mid ’80s, a decade earlier than the Senko. Other plastic stickbaits were already on the market, but none had quite dialed in the formula to this level. The heft, fine ribs, flecks of flash, salty scent, and subtle undulations added up to make something entirely new.

Yamamoto quickly realized he had something special on his hands when he watched big bass rush the bait with unusual urgency during development. As the news and popularity spread, the Senko would become the lure that provided the springboard for Yamamoto to expand his lure-making empire. He says his son chose the name out of a Japanese dictionary from numerous translations for the word “flash.”

“When you look at a Senko, it’s so easy to say it’s the dumbest, simplest lure ever created. It’s a freakin’ rubber stick,” MeatEater Senior Fishing Editor Joe Cermele told me. “In reality, though, it’s a modern engineering marvel. It’s extremely complex. Pure precision. The shape, taper, weight, density of the plastic, amount of softness, and level of buoyancy all had to be carefully refined to achieve the perfect harmony that allows this stick to produce big bass for pretty much anyone with opposable thumbs.”

Joe said he’s heard that the secret formula is guarded with “the same level of security as the recipe for Coca-Cola.” But while Yamamoto may be able to keep the details of the Senko formula under tight wraps, it couldn’t stop the shape from being closely knocked-off. There’s no shortage of copycats on the market, such as Berkley’s The General, Strike King’s Ocho, and the YUM Dinger. Joe said he’s had success with many of them, but none have proven to be better or quite as lethal as the Senko. It’s also not difficult to find Senko molds that allow home lure makers to pour their own, though Joe says most of the time the results have little in common with Senkos beyond aesthetics.

“I personally know at least six guys that bought Senko molds, a measuring cup, buckets of plastic, and even a dedicated microwave to melt it in. I’ve been given dozens and dozens of homemade Senkos over the years,” Joe said. “They all suck. Side by side on a table, you couldn’t tell some of them apart from the real deal, but you know right away on the water. They’re too stiff or too soft. They fall way too slowly or barely sink at all. They don’t have that signature Senko wobble.”

Loser or Legend?
The Senko has been on the market for 25 years now and it’s caught a lot of bass in that time. In fact, it’s caught so many that there are lots of anglers who consider fishing a wacky-rigged Senko cheating. What was once regarded in many bass fishing circles as a miracle lure has been downgraded to “the easy way out.” It’s not uncommon for the glory of an angler’s big bass to be stripped away on social media as soon as it’s revealed that it was caught on a Senko. While this might seem ridiculous, debate about the Senko has, for better or worse, infected bass culture.

“The Senko has made many anglers better than they should have been,” Oliver Ngy of Big Bass Dreams told me. “Put a hook in it, throw it in the water, and the bait does the work.”

Tournament champion Mike Iaconelli told me that you’ll hear opinions that a certain lure, bait, or fly is “cheating” anywhere you look in the angling world. Still, he said, if you were to look in the rod lockers of every pro angler’s boat at the starting line of the biggest bass tournaments in the world, from Florida to California to New York, you’d find a rod rigged with a plastic stickbait in every single one.

“I can tell you that I won the Bassmaster Classic because of it,” Mike said. “It was my follow-up lure. When a fish missed these other lures that I was power-fishing, man, I threw a stickbait back in there at ‘em. People forget about that.”

He said that though about 70% of his bass in that event came while swimming jigs and other power techniques, the rest—including the fish that won the tournament for him—came on the “magic hotdog.”

Mike said another major factor that speaks to the Senko’s greatness is its longevity as a top producer.

“I think that some baits come and go in that role, but the stickbait has been steady since the late ’90s. This one has stood the test of time. So, like right now, every dude’s got a chatterbait tied on, but will that be the case in three or four years?”

What’s the Allure?
So, why is a wacky-rigged Senko irresistible to bass? After all, there’s no rules against rigging it Texas-style, Carolina-style, on a jighead, or with a nail weight. You’ll hook bass on Senkos employing all those methods, but you’re probably not going to catch more than you would using any similar soft plastic. It’s not until you run that hook through the center of a weightless Senko, completely perpendicular to the body, that you’re delivering the crack bass can’t refuse. In the water it looks like a little bit of a lot of things, but like nothing in particular. It’s always a fun thought exercise to ask anglers what they think a Senko represents to a bass. Is it a worm? A leech? A crayfish? A dying minnow?

“I think it triggers a feeding response that’s bigger than any forage mimic that you could think of,” Mike told me. “I’m huge on match the hatch, you know, outside of trout fishing, I’m talking about bass fishing. I believe in it 100%, but I also think there are times when you can trigger a feeding response off of an action or off of a movement. And sometimes it doesn’t necessarily fit an exact category of forage. It evokes this feeding response that is, ‘oh my God, this is the easiest meal. It’s subtle, it’s wounded. It’s not trying to get away from me.’”

Mike thinks that’s the opposite of the reaction you get from jerkbaits or spinnerbaits, which require a fish to react quickly. Bass are intrigued by something that slowly flutters to the bottom then just sits there.

“It’s that response from a fish where he looks at it and a trigger happens in his mind that says, ‘I can’t pass this up.’”

As easy as it is to make fun of wacky rigging a Senko, like with most techniques there’s still a level of nuance that separates the passive from the pros. Bites are often very subtle, so it pays big dividends to watch the line as the bait sinks. Serious Senko anglers will often let the bait sit on the bottom for a long time before giving that first twitch. And when they do twitch, it’s a light lift of the rod tip rather than a big swing.

The dedicated prefer fluorocarbon line in 8- to 12-pound rather than monofilament because it sinks along with the bait instead of floating. With a medium-action rod you can still make good casts with an unweighted stick worm but get solid hooksets with steady pressure rather than a hard rip. Most anglers use 3/0 or 4/0 extra-wide gap hooks, but smaller terminal tackle can be appropriate as well.

“A lot of times we’ll say stupid Senko, but I think you can’t deny effectiveness of a bait,” Mike said. “As good as that lure is, there’s still ways to make it better and ways to be better with it. You gotta put your time in with it. It’s line control, lure control, the way it falls, hook set, the right hook, the right line, and then you throw into that mix all the different ways to fish it and rig it. It’s not just an easy lure. It’s not just putting a golden shiner on a float.”

As for me, when I bass fish I often go to the Senko last, but sometimes I’m in a hurry to get there. When nothing else is working, that oddity will still get some viewers. And putting one over on picky or pouty fish is the most satisfying fishing achievement.