The Flash: 10 Best Characters Who Only Appeared In One Episode
2. Lewis Snart
The sibling crime duo of Captain Cold (Leonard Snart) and Golden Girder (Lisa Snart) owe most, if not all their criminal and cruel sensibilities to their father, Lewis Snart. Michael Ironside imbued the character with his trademark gravitas but also a healthy dose of menace and ruthlessness.
Arguably one of the most sadistic characters in the early days of the series, Snart channelled his anger at his children, physically and emotionally scarring them as well as shaping them into the (then) present day Rogues.
The Snart patriarch spent most of his children's lives in and out of prison, and when he was finally set free, he kidnapped his offspring and forced Leonard to work for him or he would kill Lisa. At his wit's end, the Snart son secretly teamed up with Barry to ensure that the heist runs smoothly (as far as Lewis is concerned) and that Lisa lives.
Fortunately, Cisco was able to save Lisa, giving Flash time to stop the heist and Leonard the opportunity to confront and kill his father, putting an end to the particular brand of Snart toxicity and cruelty.