Launching with a tribute to the founding of Czechoslovakia a century ago, the 53rd edition of the Karlovy Vary film fest kicked off Friday amid gymnastic stunts, fireworks and a call to action by Tim Robbins, who lambasted President Trump for his maltreatment of refugee children. The actor-director joined in the commemoration of Czech freedom, paying tribute to the leading voice of the Velvet Revolution of 1989, Vaclav Havel. The courage of such men is as needful today as it was when the masses turned out in Prague to demand the end of communism, Robbins said.

Recalling his unsuccessful bid in 1985 to land the role of bullying Biff in “Back to the Future,” Robbins confessed that lately, when reading the news, he has been struck by the image of a “petulant, overblown, child monster.”

He explained that the time travel concept in the Michael J. Fox film is relevant today because a handful in power want to take America back to the 1950s. “We’re living through a Marty McFly moment,” Robbins said, but then added, “Bullies have no power without fear.”

Urging filmmakers to fight for truth and strong stories rather than succumbing to “puppets of propaganda” and the “Marvel universe,” he called on artists to “resist, resist, resist.”

The opening gala also included a tribute to Czech auteur Milos Forman, who died in April, with audiences applauding the spirit of the man fest president Jiri Bartoska said left his native country “with one suitcase and returned with two Oscars.”

The opening ceremony in the 1970s-era Hotel Thermal, which also paid homage to Richard Linklater and the indie films of the Austin Film Society, showing in the Made in Texas section, followed up with a screening of Forman’s 1965 film “Loves of a Blonde,” a key work of the Czech New Wave.

Afterward, the Czech National Symphony Orchestra performed a rousing public concert of music from Forman films, with Libor Pesek conducting Mozart pieces heard in “Amadeus” as crowds surged.

The fest, which runs through July 7, also welcomed Danish actress Trine Dyrholm (“Nico, 1988”) and Thomasin Harcourt McKenzie (“Leave No Trace”) to the official launch as packs of fans lined a sun-splashed red carpet, sundering fears that the rainy Czech summer would wash out the event.