When Ben Barnes was cast as Billy Russo, Marvel comics fans knew one thing - that the character would become Jigsaw, the Punisher's nemesis with the mangled face, at some point.
Cleverly, then, the show plays with our expectations and transforms the supervillain into a totally unrecognisable character - a charming old buddy of Frank's who's apparently a good guy. Of course, the rug is pulled halfway through the season and the truth comes out that Billy is working for Agent Orange.
Once this is out of the bag, Barnes - who previously proved he could play a b*stard in Westworld - gives a great performance as Russo's true cruel nature comes to the fore. Thanks to the added connection to Frank, Russo's a stronger character than the comics version. When the climactic moment comes and Frank rams his face into a mirror, it's simultaneously horrifying and satisfying to see the birth of the supervillain.
The only problem is that he's subservient to Agent Orange, but this should be fixed for season 2, when Jigsaw emerges to get his revenge on the Punisher.