Frank Bertinelli (Arrowverse)

Frank Bertinelli is a former mafia boss in the Arrow TV series. He is the father of Helena Bertinelli. And after ordering Michael Stanton who was Helena's fiance to be killed, she heard about it. And he started killing several members of Frank's mafia, as a form of revenge for the death of his fiance.

Biography
Frank was the mafia's crime boss and one of the targets on the list. Malcolm Merlyn blackmailed Bertinelli to help The Undertaking, in case if he refuses, he would simply leak his crimes that would be taken to the authorities. Frank had a daughter named Helena who had a fiance named Michael Stanton who was a teacher at school. Frank then had Michael killed for thinking he was leaking information to Malcoln Merlyn. However whoever was doing this, it was Helena who already intended to send the evidence to the FBI, because she was tired of him flooding Starting City with crimes and drugs, since one of Michael's students died because of a drug given the crowd.