Questions & Answers about Wir wollen den Bösen fangen.
Why is Bösen capitalized and why does it end in -n?
Bösen is a nominalized adjective, meaning it is an adjective acting as a noun to mean "the bad guy". All German nouns are capitalized, so Bösen is too. It gets the -n ending because nominalized adjectives still follow regular adjective declension rules. Here, it is the masculine singular direct object (accusative case) following the definite article den.
Could den Bösen also mean plural "bad guys"?
Not in this sentence, because of the article. While the plural noun for "the bad guys" is indeed die Bösen, the accusative article for masculine singular is den. If you wanted to catch multiple bad guys, the accusative plural article is die, making the sentence Wir wollen die Bösen fangen.
How would this sentence change if the bad guy were female?
You would change the article and the nominalized adjective to their feminine forms. The accusative feminine article is die, and the adjective ending after it is -e, so the sentence would be Wir wollen die Böse fangen.
Just to review, why is fangen at the very end of the sentence?
This is the standard word order when using modal verbs. The conjugated modal verb wollen (want) takes the second position in the sentence, which forces the main action verb fangen (to catch) to the very end in its original infinitive form.