Mi scias nenion pri la intrigo.

• Mi = I
• scias = know / know a fact
• nenion = nothing
• pri = about
• la = the
• intrigo = plot

So the structure is basically:

I + know + nothing + about + the plot

In Esperanto, -as marks the present tense.

So:

• scias = know / am knowing in the present
• sciis = knew
• scios = will know
• sciu = imperative/jussive form
• scii = the infinitive, to know

Here, Mi scias means I know.

Because nenion is the direct object of scias, and direct objects in Esperanto normally take -n.

Compare:

• nenio = nothing as a subject or basic dictionary form
• nenion = nothing as a direct object

In this sentence, the speaker is knowing nothing, so nenion is the thing being known.

No. In standard Esperanto, words like nenio, neniu, neniam, nenie are already negative, so you normally do not add ne.

So:

• Mi scias nenion = I know nothing
• Mi ne scias ion would literally be I do not know something, which is usually not what you want
• Mi ne scias ion ajn = I do not know anything

A very important pattern is:

• neni- words are negative by themselves
• don’t stack them with ne in normal Esperanto

Esperanto usually distinguishes between two kinds of know:

• scii = to know a fact, piece of information, answer, explanation, etc.
• koni = to be familiar with a person, place, book, subject, etc.

So:

• Mi scias la respondon = I know the answer
• Mi konas tiun homon = I know that person

In Mi scias nenion pri la intrigo, the meaning is about having information, so scii is the correct verb.

Pri means about, concerning, or regarding.

So:

• pri la intrigo = about the plot

It introduces the topic of the information. The sentence means that the speaker has no knowledge about that topic.

This is very common in Esperanto:

• libro pri historio = a book about history
• paroli pri io = to talk about something
• scii pri io = to know about something

La means the, so la intrigo means the plot.

Esperanto uses la when the speaker and listener can identify the thing being talked about. In this sentence, it usually means a specific plot already understood from context, for example the plot of a book, film, or story already being discussed.

Without la, pri intrigo would sound more general, more like about plot / about a plot.

Yes, Esperanto word order is fairly flexible, although Mi scias nenion pri la intrigo is the most neutral and natural order.

You may also see things like:

• Nenion mi scias pri la intrigo.
• Pri la intrigo mi scias nenion.

These can be used for emphasis. But for learners, the safest default is the simple order:

subject + verb + object + other information

So Mi scias nenion pri la intrigo is an excellent basic version.

scias is pronounced roughly STSEE-ahs.

A more careful breakdown:

• s = s
• c = ts
• i = ee
• a = ah
• s = s

So sc together sounds like sts, and scias is roughly STSEE-as, with the stress on the first syllable: SCI-as.

Yes. That is also correct and means essentially the same thing:

• Mi scias nenion pri la intrigo
• Mi ne scias ion ajn pri la intrigo

Both mean I know nothing / I don’t know anything about the plot.

The first version with nenion is often a bit more direct and compact. The second version uses ne ... ion ajn = not ... anything at all.

In meaning, pri la intrigo tells you what the lack of knowledge is about.

So the sentence is basically:

• Mi scias nenion
• pri la intrigo

You can think of pri la intrigo as adding the topic area of the knowledge. It works naturally with the whole idea know nothing.

In English, we also do this:

• I know nothing
• about the plot

So the Esperanto structure is very similar.

The dictionary forms are:

• mi = I
• scii = to know
• nenio = nothing
• pri = about
• la = the
• intrigo = plot

In the sentence, some forms are changed for grammar:

• scii becomes scias because it is present tense
• nenio becomes nenion because it is the direct object

That kind of regular ending system is one of the main features of Esperanto grammar.