Murder suspect fabricated story to help with horror film plot, lawyer says

— -- A New Jersey man accused of murdering a childhood friend made up stories about killing her as part of a horror film plot, his lawyer says.

Defense attorney Charles Moriarty made that claim Wednesday during a pretrial hearing in Freehold, New Jersey, where he unsuccessfully sought to have a judge dismiss a murder indictment against his client, Liam McAtasney.

McAtasney, now 20, strangled 19-year-old Sarah Stern, his former high school classmate, in December 2016 during a robbery that netted $10,000 before throwing her body off a bridge in Belmar, Monmouth County prosecutors allege.

McAtasney's friend, Preston Taylor, pleaded guilty to helping dispose of her body and has agreed to testify against him.

Stern's body has never been found but police discovered her abandoned car on the Route 35 Bridge with the keys in the ignition hours after she went missing.

During Wednesday's hearing at the Monmouth County Courthouse, prosecutors showed several videos of McAtasney’s talking to investigators in the days after Stern disappeared, saying he intentionally mislead authorities.

"I just know she's been trying to get away, been telling me she's moving to Canada," McAtasney said in the footage taken from police body cameras. "I mean, I know that her dad has taken money from her in the past. I think her mom was supposed to leave her money or something. I know she definitely has a lot of trust issues with her dad, so I've been trying to help out with that."

An acquaintance secretly recorded McAtasney’s saying he robbed and killed Stern, police say. But McAtasney's lawyer told the judge Wednesday his client fabricated the story for a horror movie the acquaintance was making.

Moriarty also said the acquaintance, who was not identified, told detectives McAtasney was "always making things up to be more interesting.”

"He [the acquaintance] said he always makes up stories for my films; he acts sometimes," Moriarty said, quoting what the acquaintance allegedly told detectives. "He's always giving me these great ideas and half of them are all bull."

Moriarty has asked the court to suppress the recording from McAtasney's upcoming trial.

Prosecutors are seeking life in prison without parole for McAtasney, who also faces charges of robbery, conspiracy, desecration of human remains and hindering apprehension. He has pleaded not guilty, according to ABC New York City station WABC-TV.

ABC News' Paula Faris and Morgan Winsor contributed to this report. The Associated Press also contributed reporting.