CHELSEA — To outsiders, Andrew and Vanessa MacCormack may have seemed happily married, raising their 1-year-old in Revere and working solid jobs as a union drywall installer and teacher, respectively.

But behind closed doors, prosecutors said Wednesday, Vanessa, a popular second-grade instructor in Lynn, seethed over her husband squandering their finances. She threatened to put their house on the market and file for divorce.

Tensions boiled over Saturday, when Andrew, a 29-year-old cocaine user with a $500-a-week drug habit, allegedly killed his 30-year-old wife and tried to cover up the crime, according to a chilling recitation of the accusations by Assistant Suffolk District Attorney Ian Polumbaum during the husband’s packed arraignment in Chelsea District Court.

A not guilty plea on a charge of murder was entered on behalf of Andrew MacCormack — who shook his head, cried, and loudly exhaled.

His relatives sat just feet away from a larger contingent of his wife’s family, some of whom recoiled in shock and covered their mouths when the alleged killer was brought into court. He was held without bail.

“They’re distraught and torn apart by this,’’ Polumbaum said afterward, referring to Vanessa’s family.

John Hayes, a lawyer for the accused, said his client adamantly denies killing his wife.

“It really is a completely circumstantial case,’’ Hayes said. “He’s been crying since he was arrested.’’

According to an affidavit, a Revere police officer responded to the couple’s home on Grand View Avenue at 3:35 p.m Saturday for a report of a possibly deceased person.

The officer spotted Andrew MacCormack “crying and hyperventilating’’ outside, the affidavit said, and smelled a strong odor of bleach when he entered the house before discovering Vanessa lying face up on a bedroom floor, covered in blood.

Her face had suffered blunt force trauma, teeth were missing, and she had “multiple sharp force injuries to her neck,’’ the filing said. Polumbaum said there were signs of strangulation and suffocation. The officer also saw blood drops on the floor, blood splatter on the floor and walls, and a bloody trash bag in the hallway. MacCormack told investigators he removed the bag from his wife’s head when he found her body.

He also told detectives he left with the couple’s daughter earlier Saturday so his wife could go to the gym, records show.

Investigators learned that after the murder MacCormack drove with his child to a friend’s home in Saugus to do a carpentry job, according to a statement from the district attorney’s office.

Prosecutors say MacCormack left the job site after the baby soiled her diaper, but instead of picking up a fresh diaper, he went to East Boston and took cash out of an ATM to buy cocaine.

That afternoon, MacCormack met with his drug dealer to buy $100 worth of cocaine, according to the affidavit. The dealer told police that MacCormack spent up to $500 weekly on drugs, authorities said.

Prosecutors allege that shortly before 1 p.m., MacCormack sent text messages to his wife’s phone, which was in his possession at the time, according to the DA’s statement.

While he was in Saugus, MacCormack told investigators, Vanessa’s mother called him and said she couldn’t reach her daughter. The mother said Andrew was on the phone with her when he returned home, saw his wife’s body, and told her mother, “Call 911, she’s gone,’’ the filing said.

MacCormack dialed 911 a few minutes later, according to prosecutors.

Detectives also discovered irregularities in the couple’s finances.

The affidavit said that before Vanessa MacCormack was killed there were red flags, including her $13,000 engagement ring that went missing; a replacement ring that also disappeared; Andrew MacCormack’s pawning of different items of jewelry; as well as claims that his bank account was recently hacked by someone in Thailand who stole thousands of dollars.

His wife had grown suspicious and increasingly angry, according to the affidavit.

“Don’t you dare get frustrated with me you deserve to be questioned,’’ she texted him on Sept. 15, two weeks after a prior text that read, “I hate you so much you’ve ruined [our daughter’s] life because she won’t have her parents together. . . . I’ll look into divorce lawyers.’’

Andrew responded, “Ur crazy I’m not signing anything to sell the house or get divorced.’’

Court records indicate Boston police arrested him in 2011 after being accused of dragging a previous girlfriend down two flights of stairs by her hair. That case was dismissed.

In court Wednesday, Hayes downplayed his client’s marital strife, insisting the MacCormacks were looking forward to “a life together’’ despite their problems.

He said the strong odor of bleach in the home — court records show it was poured on Vanessa’s body, leaving chemical burns, and also used to wipe down the bathroom and a television — suggests an outside intruder committed the crime and tried to cover his tracks. Andrew MacCormack’s DNA and prints, he said, would be “all over the house anyway. . . . So why would he be bleaching the house?’’

But Polumbaum said police detected no signs of forcible entry, and a kitchen knife was missing. In addition, he said, the suspect told detectives he contracted a rash after his wife switched detergents from Purex to Arm & Hammer. He pulled his shirt up to reveal a blemish that covered his torso and parts of his face and neck.

Police, though, spotted two Arm & Hammer detergent containers in the home but no other brands, suggesting she “had not recently switched brands as her husband claimed,’’ the affidavit said.

Hayes said outside court that his client’s in-laws now have custody of the couple’s daughter.

Globe correspondent Jeremy C. Fox contributed to this report. Travis Andersen can be reached at tandersen@globe.com.