Questions & Answers about Filmen i aften er rigtig sjov.
Filmen means the film / the movie.
In Danish, the definite article (English the) is usually attached to the end of the noun:
- film = film / movie
- en film = a film (en is the common-gender indefinite article)
- filmen = the film (-en is the definite ending for common gender)
So instead of saying the film, Danish packs the into a suffix: filmen.
Danish normally uses suffixes to mark definiteness, not a separate word:
- bog = book → bogen = the book
- bil = car → bilen = the car
- film = film → filmen = the film
You only use a separate demonstrative (like English this/that) when you want to point out something specific:
- den film = that/this film (often with extra emphasis)
- den film, vi så i går = the film that we saw yesterday
In your sentence, filmen already means the film, so no extra word for the is needed.