Friday the 13th: The Series (1987)

S1E17 The Electrocutioner

A wrongfully accused man faces execution in the electric chair but miraculously survives. Filled with bitterness, he purchases the chair from Lewis Vendredi. Posing as a dentist, he secures a position at an orphanage, cleverly disguising the chair as dental equipment. He then begins to murder the orphans, masking their vanishings by insisting they’ve run away. Each killing empowers him, transforming him into a living dynamo, fueling his quest for revenge against those who condemned him. The trio must find a way to neutralize him before he can strike again.