Istvan was the body guard of the Gypsy King Johnny Romano. When Istvan was a teenager, he killed another gypsy and fled. When they finally caught him, they cut out his tongue for punishment. He was allowed to work off his sentence by becoming the bodyguard and personal servant of the gypsy king. When his boss and he went to retrieve the hand of Count Petofi from a gypsy named Magda, they put her on mock trial. Magda couldn't tell them that Petofi had the hand again due to a spell Petofi had put on her. She was found guilty and Johnny sent the ghostly jurors after her. She sent them all back to their grave, but King Johnny and Istvan cornered her on Widows' Hill. Barnabas Collins arrived just in time to save her from the two gypsies. Barnabas killed Istvan by using his hypnotic powers to compell Istvan to walk off the edge of Widows' Hill when King Johnny would not give Magda to him. King Johnny Romano found out from Barnabas that Count Petofi had the hand in his possession again.
The character was played by actor Henry Baker.
Istvan appeared in four episodes in August 1969: 821, 825, 826 and 827.