Riktignok mister scenepartneren tråden, men bygger videre på innfallet.

Riktignok means something like admittedly, granted, or it is true that. It often introduces a concession: you admit one thing is true, and then contrast it with something else.

In this sentence:

Riktignok mister scenepartneren tråden, men bygger videre på innfallet.

the pattern is basically:

Admittedly X, but Y.

So riktignok sets up the first part as a fact that is acknowledged, while men introduces the contrasting or balancing second part.

This is because Norwegian main clauses normally follow the V2 rule: the finite verb comes in the second position.

When the sentence starts with riktignok, that first position is already taken. So the verb mister has to come next:

• Riktignok mister scenepartneren tråden ...

If you started with the subject instead, you would get:

• Scenepartneren mister riktignok tråden ...

Both are possible, but they place the emphasis differently. Starting with riktignok makes the concessive idea more prominent.

Scenepartneren is a compound noun:

• scene = stage / scene
• partner = partner
• -en = the definite singular ending

So scenepartneren means the stage partner, the scene partner, or more naturally in English, the scene partner / fellow actor in the scene.

This is very typical in Norwegian: instead of writing separate words, Norwegian often combines them into one compound noun.

The ending -en marks the noun as definite singular for many masculine nouns.

So:

• en scenepartner = a scene partner
• scenepartneren = the scene partner

Norwegian often adds definiteness as a suffix rather than using a separate word like the.

Literally, tråd means thread, and tråden means the thread.

But in the expression miste tråden, it is idiomatic. It means:

• to lose the thread
• to lose track
• to lose one’s train of thought

So here it is not about a physical thread. It means the scene partner momentarily loses the flow of what they were doing or saying.

Yes, å miste tråden is a common expression in Norwegian.

Examples:

• Jeg mistet tråden. = I lost track / I lost my train of thought.
• Hun mister tråden midt i setningen. = She loses the thread in the middle of the sentence.

In your sentence, mister tråden is the present tense form:

• mister = loses
• tråden = the thread

Bygger videre på means builds further on, develops further from, or continues based on something.

It comes from:

• bygger = builds
• videre = further / onward
• på = on

So bygge videre på noe is an expression meaning to take an idea, suggestion, or starting point and develop it more.

In natural English here, it might be:

• continues from the impulse
• builds on the idea
• develops the spontaneous idea further

Innfallet is the definite form of innfall.

• et innfall = an impulse, whim, sudden idea
• innfallet = the impulse / the sudden idea

In this context, innfall probably means a spontaneous idea or unexpected inspiration that comes up in the scene.

So bygger videre på innfallet means that the person continues developing that spontaneous idea.

Because the sentence refers to a specific impulse or idea already understood from the context.

Compare:

• et innfall = an impulse / a sudden idea
• innfallet = the impulse / the sudden idea

Norwegian often uses the definite form when the thing is identifiable in the situation, even if English might sometimes sound more natural with an.

The subject is understood to be the same as in the first clause: scenepartneren.

So the full version could be:

• Riktignok mister scenepartneren tråden, men scenepartneren bygger videre på innfallet.

But repeating the subject would sound unnecessary. Norwegian often omits the subject in the second coordinated clause when it is the same as the first one.

So:

• ..., men bygger videre på innfallet means
• ..., but [the scene partner] builds further on the impulse

Yes, that is grammatically possible. It would be more explicit:

• Riktignok mister scenepartneren tråden, men scenepartneren bygger videre på innfallet.

But because the subject is the same in both clauses, Norwegian usually prefers to leave it out in the second clause unless there is a reason to emphasize or clarify it.

Because men joins a new coordinated clause, and when the subject is omitted because it is understood, you simply get:

• men bygger videre på innfallet

If the subject were expressed, normal word order would be:

• men scenepartneren bygger videre på innfallet

The conjunction men itself does not force inversion in the way that sentence-initial adverbials do.

Both are present tense:

• mister = loses
• bygger = builds

The infinitives are:

• å miste = to lose
• å bygge = to build

So the sentence describes something happening in the present, or it may be using the present tense for a general observation or vivid narration.

Because these are two different verb expressions.

1. å miste tråden

   • This is a fixed expression without a preposition.
   • Literally: to lose the thread

2. å bygge videre på noe

   • This expression requires på
   • Meaning: to build further on something

So the preposition is not random; it belongs to the verb phrase bygge videre på.

It is not extremely formal, but it does have a slightly polished or written feel, especially because of riktignok.

A more conversational alternative might use words like:

• jo
• sant nok
• or a simpler structure

But riktignok ... men ... is a very normal and useful written pattern in Norwegian, especially in analysis, commentary, or descriptive prose.

Yes, innfall can sometimes suggest a whim, a sudden impulse, or an idea that appears unexpectedly. Depending on context, it can sound:

• neutral: a sudden idea
• creative: an inspired impulse
• slightly negative: a whim

In this sentence, it most likely sounds neutral or creative: a spontaneous idea that the scene partner is able to develop further.

It follows a common concessive pattern:

• Riktignok
  • statement 1
• men
  • contrasting statement 2

So the logic is:

• Admittedly, the scene partner loses the thread, but [they] continue building on the impulse.

This kind of structure is very common in Norwegian when you want to acknowledge a weakness or problem while highlighting a positive or compensating point.