(CNN) -- It started with a father sending text messages during the previews of an afternoon movie.
It ended with the 43-year-old father shot dead amid the theater seats, and a 71-year-old retired police officer in custody.
Charged with second-degree murder, the ex-cop is scheduled to make his first court appearance Tuesday at 1p.m.
The encounter between the victim and the shooter began during the previews ahead of the Peter Berg film "Lone Survivor" at the Grove 16 theater in the Tampa suburb of Wesley Chapel. The former officer, Curtis Reeves, was with his wife and sat behind Chad Oulson and his wife. Chad Oulson was using his cell phone and Reeves told him to put it away, according to police and witnesses.
The two men began to argueand Reeves walked out of the theater. Police said Reeves was going to complain to a theater employee, according to the police report.
When Reeves returned, witnesses and authorities said that Oulson asked him if he had gone to tell on him for texting. Oulson reportedly said, in effect: I was just sending a message to my young daughter.
Charles Cumming and his adult son were two seats away. Cummings said that when Reeves returned to the theater, he didn't return with a manager. "He came back very irritated," Cummings recalled.
Voices were raised. Oulson threw a bag of popcorn at Reeves, according to a police report, and then the former Tampa Police Department officer took out a .380 semi-automatic handgun and shot Oulson.
Oulson's wife Nicole raised her hand just before the shot was firedand the bullet went through her hand and into her husband's chest, authorities said.
As Oulson staggered and fell, "He said, 'I can't believe I got shot," the younger Cummings recounted. "Blood started coming out of his mouth. I was trying to hold him up. He just fell down."
Nicole Oulson suffered a non-life threatening wound. Her husband died after being taken to the hospital.
During an interview with Reeves with his arrest, and after the former cop was read his Miranda rights, Reeves admitted to firing his weapon at the victim because "he was in fear of being attacked," according to the police report.
Reeves told police that Oulson had hit him with what the police report describes as an "unknown object."
Witnesses told police they saw no punches being thrown during the incident, according to the report.
There were 25 people in the movie theater. After the shooting, some made valiant efforts to help Oulson, who later died at a hospital, and to make sure no other people were hurt.
An off-duty deputy sheriff from Sumter County rushed over to make sure no more shots were fired and that the shooter was not going to get up.
One of two nurses in the audience ran to Oulson's side and performed CPR until paramedics arrived. An autopsy will be conducted Tuesday.
"I can't believe people would bring a pistol to a movie," said Cummings, a Vietnam War veteran who was celebrating his birthday by spending the afternoon with his son.
Reeves retired in 1993 as a captain with the police department in nearby Tampa. He was alsodirector of security at Busch Gardens until 2005, CNN affiliate Bay News 9 reported. Police told CNN that Reeves was instrumental in establishing the department's first Tactical Response Team.
CNN is attempting to obtain Reeves' full law enforcement employment record.
It's unclear if Reeves has retained an attorney.
A neighbor told Bay News 9 that Reeves was a nice guy.
"Always smiling. I've never seen him angry," Bill Costas said. "If I needed help with something, he was always there."
Costas said he feels bad for the wives and families of both men.
Meanwhile, Cobb Theatres, which operates the Grove complex, released a statement: "This was an isolated altercation between two guests that escalated unexpectedly. The safety, security and comfort of our guests and team members are always our top priorities, and we are truly heartbroken by this incident."
A list of prohibited items and behavior in their theaters are on the theater website. Among them: no cell phone use, including texting, in the theater auditorium. And no weapons allowed.
By Steve Almasy and Ashley Fantz
CNN's Suzanne Presto contributed to this report.