trilogy
US /ˈtrɪl.ə.dʒi/
UK /ˈtrɪl.ə.dʒi/

1.
trilogía
a group of three novels, films, or plays that are complete in themselves but are related to each other in subject matter, or by a common author or characters
:
•
The Lord of the Rings is a famous trilogy.
El Señor de los Anillos es una famosa trilogía.
•
She plans to write a trilogy of historical novels.
Ella planea escribir una trilogía de novelas históricas.