What other great mysteries have finally been solved?

In 1981, a Soviet submarine ran aground in Swedish waters.

This was a huge deal, although the Soviets claimed the sub was in distress and didn't purposefully enter Swedish waters.

Basically everyone in Sweden saw it as evidence that their waters were being invaded by spy subs. Plus,

they did some snooping of their own and determined that the sub was emitting radiation,

meaning it had nukes on board. So they went along with the Soviets clearly false claim about

accident and helped get the sub out of there, but panic was in the air. So the Swedes did exactly what you'd expect

and they prepared for more Soviet subs. I mean, when you see one Soviet sub, surely there are more,

right? So Sweden developed advanced acoustic technology to detect subs, and they created a plan

to basically seal off the waters when they heard a sub. And wouldn't you know it, a year later, they found a Soviet sub.

Well, they didn't find it, but they absolutely heard it.

And they cut off the bay and figured they just had to hunt the sub down.

But after a month, they couldn't.

They gave up and reopened the bay, but they assumed the sub found a way out, but they'll get it next time, and then it happened again, but they couldn't find it again, and then again, with no clear pattern for a decade. What the heck?

Thankfully, the Berlin Wall fell and the Soviet Union collapsed. So, no more subs, right?

Niet. Because the Russian subs are still coming. Wait, what? Okay, so now nothing is making

sense. At this point, the Swedish military bought in outside experts to figure out what was

happening. This included oceanographer types, who were obvious experts in the surrounding waters.

The military then played the audio evidence of the Soviet submarines, only to be told they

weren't submarines at all. They were fish, and the propeller-like sound was water being released

from their swim bladders. And that is the story of how the Swedish military spent 10 years and

tens of millions of dollars chasing gassy, tooting fish. This is a personal family mystery that

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