В конце фильма герои целовались под дождём, и весь зал молчал.

В конце is a very common phrase meaning at the end. The noun конец becomes конце after в, and the thing whose end it is goes in the genitive: фильма = of the film.

So the structure is:

в конце + genitive

Examples:

• в конце книги = at the end of the book
• в конце урока = at the end of the lesson

So в конце фильма literally means at the film’s end.

Not necessarily in the English sense of heroic people. In Russian, герой фильма, герой книги, герой романа often means character, especially an important one.

So in this sentence, герои is best understood as the characters or the main characters.

Целовались comes from целоваться, which is a reflexive verb. Here it means to kiss each other.

So:

• целовать = to kiss someone
• целоваться = to kiss, to be kissing, often to kiss each other

Because the subject is plural, герои, the meaning is naturally reciprocal: the characters were kissing each other.

The ending -сь is the reflexive marker.

This is an aspect question.

• целовались is imperfective
• поцеловались is perfective

Here целовались is used because the action is presented as ongoing or as part of the scene. It paints the moment: the characters were kissing under the rain.

If you said поцеловались, it would sound more like a completed event: they kissed.

So the sentence is cinematic and descriptive:

• герои целовались = the characters were kissing
• герои поцеловались = the characters kissed

The preposition под takes the instrumental when it means physical location: under something.

So:

• под столом = under the table
• под деревом = under the tree
• под дождём = under the rain / in the rain

In natural English, под дождём is usually translated as in the rain.

Also, дождём is the instrumental singular form of дождь.

The ё matters both for pronunciation and stress. Дождём is pronounced with stress on the final syllable.

So:

• дождь = rain
• дождём = in the rain / under the rain

In printed Russian, ё is sometimes replaced by е, so you may also see дождем, but it is still understood as дождём.

Because зал is singular.

• весь = whole, all of a singular masculine noun
• все = all, everyone, or plural all

So:

• весь зал = the whole hall / the entire audience
• все люди = all the people

Here весь зал is a singular expression meaning the auditorium as a whole, or by extension the audience in it.

It can suggest both, and that is very natural in Russian.

Literally, зал is the hall or auditorium. But in contexts like cinema, theater, or concerts, весь зал молчал often means the whole audience was silent.

So Russian is using the place to refer to the people in it, just as English might say:

• The whole theater went quiet
• The room fell silent

Because the grammatical subject is зал, and зал is singular masculine.

Russian verbs agree with the grammatical subject, not with the idea of how many people are involved.

So:

• зал молчал = the hall / audience was silent
• герои целовались = the characters were kissing

That is why one verb is plural (целовались) and the other is singular (молчал).

Russian does not have a separate tense form like the English past continuous. Instead, it often uses the past tense of an imperfective verb to express an ongoing or background action.

So:

• целовались can mean kissed or were kissing, depending on context
• молчал can mean was silent or kept silent

In this sentence, both verbs are descriptive background actions in a scene, so English naturally uses:

• were kissing
• was silent or sat in silence

Because и is joining two separate clauses, each with its own subject and verb:

• герои целовались под дождём
• весь зал молчал

When и connects two full clauses like that, Russian normally uses a comma.

Yes. Russian word order is flexible, and changing it often changes emphasis rather than basic meaning.

The given sentence is neutral and natural: В конце фильма герои целовались под дождём, и весь зал молчал.

You could also say:

• Герои в конце фильма целовались под дождём...
• Под дождём герои целовались в конце фильма...

These versions are grammatically possible, but the emphasis shifts. The original starts with в конце фильма, which sets the scene first: at the end of the film. That is a very natural storytelling order.