Ryan Pourciau is either a calculating killer who fantasized about torturing and slaying members of his ex-girlfriend’s family or a naive and scared young man who the same family manipulated and terrorized.

In the coming days, a Tangipahoa Parish jury will have to choose between the starkly different portraits drawn by a prosecutor and defense attorney as they delivered opening statements Wednesday in Pourciau’s second-degree murder trial.

In April 2013, April Vander Linden, 39, was shot and killed in her Ponchatoula home. The shooting prompted a massive search for Pourciau, now 20, and forced Ponchatoula High School to go into lockdown for two days until he was found, hiding under a bed in the Vander Linden home.

In their opening statements, Assistant District Attorney Angel Monistere and defense attorney Michael Thiel offered jurors radically different accounts of events leading to Vander Linden’s death. The prosecutor focused on the brutality of the killing and the planning it took, while Pourciau’s attorney emphasized the clashes between the families in the months preceding the shooting.

Pourciau and the Vander Lindens lived in the same subdivision, and in fall 2011 when he was a junior at Ponchatoula High, he rode the bus with the Vander Lindens’ daughter, a freshman. They became friends and eventually started dating, the attorneys explained.

They had a “physical, intimate relationship” that included sharing explicit photos, for about a year and a half, Thiel said. But around October 2012, April Vander Linden saw “evidence” on her daughter’s phone and ordered she break things off with Pourciau, Thiel said.

The girl openly complied with her parents but secretly kept having sex with Pourciau, telling him that she loved him and wanted to get married, “playing him along” for months after, the defense lawyer said.

In Monistere’s telling, the relationship had “fizzled out” by December 2012, and was over for good by February 2013, by which time the girl was dating others.

Pourciau couldn’t take it, and that month, the girl’s father, Brett Vander Linden, filed for a restraining order on his daughter’s behalf, saying Pourciau shoved, stalked, harassed and threatened her, the petition states.

Pourciau left a threatening voicemail stating that he was going to kill the girl if she did not return his call, according to the petition.

Brett Vander Linden wrote he tried to reach out to Pourciau’s father to put an end to the harassment. However, Thiel, the defense lawyer, said that as the Vander Lindens left the Pourciau family’s home, April Vander Linden wheeled around and darkly remarked, “We have guns.”

They visited the home again, and again behaved threateningly, Thiel said. In fear, he said, Pourciau bought a bullet-proof vest.

The month after the restraining order was issued, Pourciau posted an explicit image of his ex-girlfriend on Facebook, Monistere said, which led to his arrest on a child pornography count.

Around this time, Thiel said, Pourciau began to feel the walls close in as the restraining order affected whether he could go to school and forced him out of his home for a short time.

A child pornography conviction could spell jail time, a lifetime on the sex offender registry and the death of his dream to join the military, Thiel said.

He went to the Vander Lindens’ house the day of the shooting not to kill, but to scare them into leaving him alone, the defense attorney said.

Monistere, the prosecutor, told jurors that they would hear from classmates who said Pourciau told them that he couldn’t stop thinking about torturing members of the Vander Linden family.

On the day of the shooting, Pourciau left a jacket near the house that his ex-girlfriend recognized and reported to law enforcement, Monistere said. He then hid nearby to see how long it would take deputies to arrive at the home, the prosecutor said.

After the deputy left, and while April Vander Linden was alone in the house, Pourciau stormed in “dressed to kill,” wearing a bulletproof vest, carrying two knives, nylon ties, a handgun and extra ammunition, Monistere said.

Pourciau put a loaded semi-automatic into April Vander Linden’s chest and pulled the trigger, the prosecutor said, and when she tried to get away, he put it to her head and “blew her brains out.”

“He entered that property cool, calm and collected when he pulled that trigger. ... This man on a mission had one goal and one goal only — to torture and kill April Vander Linden,” Monistere said.

The trial is expected to last several days and into next week, as Judge Jeff Johnson indicated more than 50 witnesses would be called to testify.

Follow Steve Hardy on Twitter, @SteveRHardy.