‘The Thread’ traces social media in Marathon Bombing coverage

A scene from Greg Barker’s documentary “The Thread.”Content Media

Social media played a key role in keeping the world informed and misinformed about what was happening during the chaos following the Boston Marathon bombing. Greg Barker’s brisk, stimulating documentary “The Thread” suggests that, whether for better or worse, this coverage changed for good the way news is reported.

Barker interviews some of the more prominent figures involved in the phenomenon — including Gavon Laessig of Buzzfeed, the pop culture website that found itself posting updates of the attack instead of its usual ephemera. And Erik Martin of Reddit — the vox populi of the Internet whose myriad contributors provided both up to-the-minute facts and viral falsehoods.

But he also includes more obscure participants who could probably be the subject of their own documentaries. Like the nerdy screenwriter who lives in a basement apartment with his cat. He took on the job of monitoring a “subReddit” thread focused on finding the bombers and found himself overwhelmed by the hate speech and irresponsible accusations. Or the Emerson freshman who witnessed the bombing and then decided to see for himself the manhunt in Watertown, posting updates of his observations.

“This was something I filmed,” he says proudly, watching footage of a police press conference on his iPad. “Right in front of all the news reporters. I think old media is going to die.”

“The Thread” will be released on VOD on Monday. For more information go to www.contentmediacorp.com

Longest running

There are marathons, then there are ultramarathons. While the former measures in at the traditional 26.2 miles, the latter can stretch on seemingly forever. The late Micah True excelled at ultramarathons, and practiced his sport in Mexico’s Copper Canyon, home of the Tarahumara Indians, legendary for their running prowess. In honor of the tribe, True founded a 50-mile ultramarathon, the subject of Sterling Noren’s documentary “Run Free: The True Story of Caballo Blanco.” The film makes its world premiere on Thursday at the Revere Hotel.

For more information about the film go to www.runfreemovie.com/trailer

Family photos

In his new film, documentarian Peter Kunhardt, winner of an Emmy for “JFK: In His Own Words” (1988), shares the photos and artifacts gathered by his family over five generations. Sounds like it could be a dull evening with dusty family albums — except that the subject of the collection is Abraham Lincoln.

Described in Kunhardt’s voice-over as a “glorious burden,” the family hobby has preserved such iconic images as those used on the penny and the $5 bill.

Kunhardt’s “Living With Lincoln” parallels history with the microcosm of a family chronicle. It can be seen Monday at 9 p.m. on HBO.

For more information go to www.hbo.com/documentaries#/documentaries/living-with-lincoln

Framing father

A scene from Viko Nikci’s “Coming Home.”

The circumstances surrounding Angel Cordero’s arrest and conviction for attempted murder alone would suffice to make a compelling documentary. An innocent bystander, he was grabbed by the NYPD and found guilty of the crime despite the lack of evidence. Even when the actual culprit confessed, Cordero’s appeal was denied and he served the remainder of his 13-year sentence.

The injustice, however, doesn’t bother Cordero as much as the estrangement from his now 16-year-old daughter. Even though her father was innocent of the crime, she believes he is guilty of abandoning her. In his documentary “Coming Home,” Viko Nikci shows Cordero’s efforts to earn back his daughter’s love.

The film screens Sunday at 7 p.m. as part of the newportFILM program at the Casino Theatre, 9 Freebody St., Newport, R.I. Angel Cordero will be present to answer questions after the screening, and a reception will precede it at 6 p.m.

For more information go to www.newportfilm.com/film-events/films/coming-home

Big family

They don’t make them like “Giant” (1956) anymore, and given the quality of some recent releases, it’s Hollywood’s loss.

Adapted by George Stevens from an Edna Ferber novel about a family of Texas cattle ranchers, the film starred Rock Hudson as the patriarch, Elizabeth Taylor as his wife, and James Dean as the bitter surrogate son.

That’s a lot of star power to hit the tiny Texas town of Marfa, where the film was shot. In his documentary “Children of ‘Giant,’ ” Hector Galán pays a visit 60 years after all the glitz and glamour left. Though in part a pulpy melodrama, “Giant” also touched on themes of gender and racial inequality, which, as Galán’s film demonstrates, are issues yet unresolved.

It is part of the PBS series VOCES, and can be seen on Friday at 10 p.m. on WGBH.

For more information go to video.pbs.org/video/2365438216/

Big brother

This year’s best documentary Oscar winner, Laura Poitras’s “Citizenfour,” investigates the story of Edward Snowden, who leaked classified documents revealing the extent to which Americans are under surveillance by their own government. It screens as part of the Emerson “Bright Lights” series. A discussion follows with Emerson professor John Gianvito, who has made his own politically provocative films such as “Profit Motive and the Whispering Wind” (2007) and “Far From Afghanistan” (2012).

The screening takes place at 7 p.m. at the Bright Family Screening Room, 559 Washington St., Boston.

For more information go to web.emerson.edu/brightlights/event/citizenfour