HEY GUYS, I'M FROM THE MENTALIST PRODUCTION TEAM. THE KILLER IN FACT IS BRETT PATRIDGE, BUT THE TWIST IS THAT HE IS JANE'S OLDER BROTHER. HE HYPNOTISED JANE IN THE PAST TO FORGET ABOUT HIM IN PAST AFTER HE KILLED HIS FATHER. 
JUST A LITTLE SPOILER FOR THE FUTURE........