Their story is told in the novel In the Time of the Butterflies by Julia Alvarez and in the equally excellent film by the same name starring Salma Hayek, Edward James Olmos and Lumi Cavazos.
In searching for a film trailer, I found two that were created by students;
The one by Kevin Peralta posted a video labeled as an official trailer, though it does not does not actually show the film at all. Rather short takes of high-school students reenacting some of the film's key moments provide a moving introduction to the story.
A literature student identified only as Travis has also posted a compelling railer by editing clips for the actual film.
Note: I use the exclamation ¡Presente! in the title of this post in reference to the way those who are killed or disappeared by governments in Latin America are recognized at ceremonies or rallies. The term ¡Viva! is sometimes used, but often not quite accurate for those whose fates are unknown. So when someone like the Mirabel sisters is remembered, the word ¡Presente! (or its plural) is shouted, signifying their ongoing presence in the movement.
In recognition of this practice, the newsletter of SOA Watch is known as ¡Presente! It documents ongoing efforts to close the School of the Americas at Fort Benning, Georgia, which has a long, bipartisan history of training U.S. allies in the suppression of democratic movements.