Whacked out David Laffer was on a desperate mission for painkillers, blood pressure medicine, anti-nausea pills and muscle relaxants, so he and his wife Melinda Brady could get high.
Armed with a pistol the 33-year-old army vet walked in and lined up his victims, store workers Raymond Ferguson, 45, and Jennifer Mejia, 17, and customers Bryon Sheffield, 71, and Jamie Taccetta, 33.
Then in cold blood he put a bullet into each of their heads, before jamming the pills in the backpack and running out to his waiting wife, Melinda Brady who acted as getaway driver.
Laffer will now serve five consecutive life terms.
Suffolk County District Attorney Thomas Spota called the killings among the most gruesome in the history of the county.
Laffer has since said in a jailhouse interview that the first shot went off accidentally and when he realized what happened, he proceeded to kill the others. Prosecutors say Laffer and his wife staked out several pharmacies before settling on Haven Drugs, a tiny family-owned business on an out-of-the-way suburban street.
Laffer has said he expects he will be killed in prison.
"I'm not even under any illusions that I'd make it 15 years," he told Newsday in a September interview.