In its 18th year, the Martha’s Vineyard Film Festival is still finding ways to push boundaries.

“We’re really trying to figure out how to challenge our patrons and ourselves,” said festival founder Thomas Bena.

With the help of SailMV, the festival aims to be zero waste for the first time, and all but two of the 20 films in this year’s line-up will be followed by discussions with filmmakers, film subjects or influential thinkers. Organizers see that discourse as an integral part of the festival.

“I think experience, that is the essence of this summer,” said Brian Ditchfield, artistic director of the festival.

Both men said the films have been carefully chosen to adhere to the festival’s mission to spark discussion, debate and action. “These films are our times, encapsulated,” Mr. Bena said. “We’re hoping people walk out with a sense of wanting to take action where they live.”

Movies will be shown on Wednesday evenings throughout the summer at the film festival campus at the Chilmark Community Center, with other screenings taking place at various venues around the Island. The season opens on Saturday, July 7 at the Tabernacle in Oak Bluffs with The Final Year, a documentary directed by Greg Barker about the major architects of United States foreign policy during President Obama’s last year in office. There will be a post-screening discussion with former Secretary of State John Kerry, which will be moderated by Mr. Bena.

“I’m really nervous,” Mr. Bena admitted.

Another high-profile guest this summer will be Patrisse Cullors, co-founder of the Black Lives Matter movement. Ms. Cullors spoke at the festival last year and will return this year to discuss the docu-series, Resist, directed by Tani Ikeda, Mobolaji Olambiwonnu and Natalie Johns. The event will be part of one of this season’s Monday night fundraising screenings at the Beach Plum Inn in Menemsha.

“She is literally in the center of this debate about race in America, about mental illness in America, and about incarceration,” Mr. Bena said.

The film follows Ms. Cullors’ and other activists’ work to stop the construction of a new jail in Los Angeles county. Ms. Cullors will be joined by journalist Charlayne Hunter-Gault.

Resist is one of eight films in the summer series directed or co-directed by a woman.

“For years it was really hard to find films directed by women,” Mr. Bena said. “That’s changed in the last decade, dramatically I would say. You’ll see a through-line in the programming of powerful women.”

Callie Khouri, who wrote the 1991 film Thelma and Louise, will join the festival for one of the Monday night dinner series at the Beach Plum Inn with a screening of that film.

Festival managing director Hilary Dreyer said she is particularly excited about the film, Time for Ilhan, directed by Norah Shapiro. The documentary is about Somali-American Ilhan Omar’s historic campaign to become a Minnesota state representative. The film will be the last of the season on August 22.

“You just see the media cling onto every part of her identity whether she acknowledges it as part of her identity or not,” Ms. Dreyer said.

A guest speaker sure to deliver on debate is Harvard law professor and Vineyard resident Alan Dershowitz, whose most recent book is entitled The Case Against Impeaching Trump.

Mr. Bena was recently informed — on the Chilmark General Store porch — that Mr. Dershowitz has joined the legal team for film producer Harvey Weinstein, and he said that revelation gave him serious pause. But the discussion will go on as planned, and will also feature labor lawyer and anti-Trump activist Jules Bernstein.

“I really think that our platform of discussion, debate and action, not for the easy things that we all agree on, but the sticky things, that’s what keeps me going,” Mr. Bena said.

Mr. Dershowitz will be the featured guest following a screening of American Chaos, a film directed by James Stern that follows the 2016 election from the perspective of conservatives in red states.

“The film is about how you listen to the other side, listen to conservative Americans who voted for Trump,” Mr. Bena said. “It’s a beautiful film.”

The series includes four free community screenings. Keepers of the Light, a documentary directed by Liz Witham and Ken Wentworth, tells the story of the Gay Head Light and its 129-foot move away from the eroding Aquinnah cliffs. It will be screened for free at the Aquinnah Circle July 19.

In another first, the festival will partner with the Martha’s Vineyard Agricultural Society for a drive-in screening of E.T. on July 31 held at the Agricultural Hall in West Tisbury.

“We’ve been trying to do a drive-in since 2012,” Mr. Ditchfield said.

The free children’s Cinema Circus is back on Wednesdays with its cast of fanciful characters such as Ellie the Elephant. Children’s activities start at 5:30 p.m. and dinner follows at 6:30 before the 8 p.m. screenings.

Ms. Dreyer said Wednesday night screenings are the gems of the season.

“It’s just such a beautiful blend of people of all ages, there for different reasons, celebrating summer,” she said.

For ticket information and a full summer schedule visit tmvff.org.