A Winthrop Harbor couple charged in connection with a heroin deal that led to an overdose death pleaded guilty Monday in Lake County Circuit Court.

Andrew Matovich, 41, was sentenced to 18 months in prison, while his girlfriend, Leah Styles, 39, was placed on probation for two years.

Assistant State’s Attorney Matthew Demartini said the couple, who were residents of a hotel on Sheridan Road, met with Robert Eubanks, 24, and Eubanks’ girlfriend at the hotel on the night of Feb. 13.

Matovich and Styles took money from Eubanks and Eubanks’ girlfriend, both of Kenosha, Wis., and drove to Waukegan where they purchased a small amount of heroin.

Matovich and Styles returned to the hotel where the heroin was split between the four and consumed, Demartini said.

Police were called later that night when Eubanks went into convulsions and died, Demartini said, and added that Matovich and Styles told police they had purchased the heroin in Waukegan.

Demartini said Eubanks’ death remains under investigation, and others could be charged in the case.

Matovich pleaded guilty to possession of a controlled substance, and Styles pleaded guilty to delivery of a controlled substance during hearings before Associate Judge George Bridges.