Learn Italian: La prima scena del film è tristissima. - The first scene of the movie is very sad.

The regular adjective for sad is triste. To make it "very sad" using the absolute superlative, you drop the final vowel -e and attach the -issimo suffix.

Why does tristissima end in -a here instead of -o?

Adjectives with the -issimo suffix must still agree in gender and number with the noun they describe. Because it describes la prima scena (a feminine singular noun), the ending changes to -a.

Does the word prima (first) also change depending on the noun?

Yes! Ordinal numbers like prima act like regular adjectives. Because scena is feminine singular, we use prima. If you were talking about "the first movie", it would be masculine: il primo film.

Why do we use del instead of just saying di il film?

In Italian, the preposition di (of) almost always merges with the definite article that follows it. When you combine di and il (the), they blend together to form the single word del.