Drugs, greed and friendships gone awry are at the center of a Lake County double murder case.

According to testimony during his ongoing preliminary hearing, Robby Alan Beasley killed a Maine couple he had earlier befriended because he was convinced they had stolen some of his marijuana.

Afterwards, Beasley had second thoughts, said Lake County prosecutor Art Grothe, citing testimony at the hearing.

"Beasley began thinking somebody else really ripped him off and started threatening other people," Grothe said.

Beasley, 30, is charged with two counts of murder in connection with the deaths of Frank and Yvette Maddox, 32 and 40, said Lake County prosecutor Art Grothe. Also charged is Elijah Bae McKay, 28, Beasley's longtime friend and a prime witness in the case against him.

"They talked about whether or not (Beasley) was going to kill them and how," Grothe said.

A preliminary hearing for McKay has not yet been set.

McKay also testified that he provided the 9 mm handgun that Beasley used to kill the couple, he said. McKay claims he did not know Beasley was going to kill the pair who, like Beasley and McKay, were former Maine residents, Grothe said.

Beasley became friends with them after serving time in a Maine prison with Frank Maddox, according to testimony at the hearing.

In 2009, Beasley invited them to move to Lake County to help him trim marijuana. They also worked for McKay and lived in a tent on his land until he fired them.

McKay testified they were troublesome employees,Grothe said. They moved in with Beasley, who had an indoor growing operation near Lower Lake. They also had a falling out with him and moved out.

Grothe said McKay testified the couple became volatile and angered a number of people after they fell in with a crowd that used methamphetamine.

Beasley allegedly shot the couple in January 2010 after luring them with a phony request for a ride to the airport, law officials said.

Their bodies were discovered down a 20-foot embankment along a road east of Lower Lake in March.

The preliminary hearing is expected to conclude Thursday.