NEWTOWN - For the first 40 seconds in the new Sandy Hook Promise public service announcement, kids play along with the satirical theme of being grateful for the new classroom supplies that are helping them survive a mass shooting.

New headphones are great for studying during gunfire, one student says matter-of-factly, as mayhem breaks out in the library.

Another student sprints down the hallway to flee gunfire and a falling classmate, grateful because, “These sneakers are just what I need to start the new year.”

But after a girl demonstrates that her sock makes a great a tourniquet on a badly bleeding friend, the kids can play along no more.

“These new socks? They can be a lifesaver,” the girl says with grim determination.

The final scene shows a sobbing girl bravely trying to be grateful for the new cell phone that allows her to text her mother for the last time, as the shooter’s footsteps approach.

“It’s back to school time,” the video concludes in white text on an all-black background. “And you know what that means.”

Mark Barden, a co-founder of Sandy Hook Promise and the father of first-grader who was slain in the 2012 massacre of 26 students and educators at Sandy Hook School, said the point of the PSA was to shock people into action who have grown apathetic to mass shootings.

“The idea originated from the horrible reality that people are selling bullet-proof backpacks as school supplies - which is just insane,” said Barden, whose Newtown-based nonprofit has become one of the premier gun violence prevention groups of its kind in the country. “So we turned that message on its head,”

The hope is more people will learn about the nonprofit’s Know the Signs programs, which teach the warning signs of violence and self harm, and recommend ways to intervene.

“Subconsciously accepting shootings as regular occurrences has become the “new normal” at schools and public spaces across the country,” Sandy Hook Promise said in a prepared statement. “By focusing on early identification, action and intervention it is possible to prevent tragedies.”

The PSA’s release comes six weeks after back-to-back mass shootings in Texas and Ohio renewed calls for gun policy reform.

Unlike previous Sandy Hook Promise public service announcements that portray everyday American classroom scenes before revealing the school shooter to the unsuspecting viewer, the new “Back to School Essentials” PSA makes the case right away how ironic it is for kids to use back-to-school supplies to survive a shooting.

“These scissors really come in handy in our class” says a middle-school aged girl in a dark classroom, holding the scissors like a knife as the school shooter approaches her class.

The PSA is lastest in a series of gripping videos by Sandy Hook Promise, depicting everyday American life, with gun violence hiding in plain sight.

In 2016, “Evan” took viewers through a typical high-schooler’s secret correspondence with an admirer while missing the signs that a student was preparing to shoot students.

More recently, a PSA in December took viewers through the everyday scenes of a high school day from the viewpoint of a student who turns out to be the shooter. He shouts into a crowded auditorium of peers “Look at me!” The video fades to the message, “Most people only notice a shooter once it is too late.”