Hidden Ersatz infinitive or double infinitive?

Question

In Remarque's "Im Westen nichts Neues" ("All Quiet on the Western Front" in Wheen's translation)

I encountered this clause:

Wir werden nachts versuchen müssen.

Which translated with deepl means:

We will have to try at night.

But I have only seen the double infinitive apply with haben. Basically, can it work with any auxiliary?

If there is an implied "zu" in there like this:

Wir werden nachts zu versuchen müssen.

Then that would make sense. But then my follow up question if that is the case, is there a way to tell when someone is speaking they have an implied "zu" in a clause or do you just need to be exposed enough to pick up the contextual clues?

Answer 1

Actually, what I'm really missing in this sentence, is the "es" as object for "versuchen":

Wir werden es nachts versuchen müssen.

But this is not related to what you think is a double infinitive.

Let's start in present tense:

Wir müssen es versuchen.

Präteritum:

Wir mussten es versuchen.

Perfekt:

Wir haben es versuchen müssen.

Futur:

Wir werden es versuchen müssen.

So this seemingly double infinitive is simply an infinitive caused by a modal verb, which is put into future tense.

Answer 2

If you qoute a sentence wrong, do not be suprised when your questions get wrong or incomplete answers.

The phrase "Wir werden nachts versuchen müssen" can only be found once in the book, in chapter 6 (p. 105 in the Kiepenheuer & Witsch 1984 edition), and is not a complete sentence. The whole sentence reads:

Wir werden nachts versuchen müssen, ihn nach hinten zu bringen.

As the other answers noted, your quote was missing the object. The object is right there, in the form of an infinitive group. For the grammar of the first half of the sentence, the answer by user1934428 describes it correctly.

Answer 3

The other answer is right that the real reason why this sounds odd is that there's an object missing: what do you want to try at night? I suppose in theory "wir werden nachts versuchen müssen" is grammatical because the context might be something like "wir haben jetzt dreimal versucht, tagsüber reinzukommen, das hat nicht funktioniert, wir werden nachts versuchen müssen", but even that sounds better with "es" before "nachts".

There is definitely no "zu" missing. Neither after "werden" nor after "müssen" do you ever use a "zu" infinitive. Ich muss arbeiten, ich werde arbeiten, so therefore also: wir werden es versuchen müssen, there is no way to add "zu" to this and have it still be grammatical.