Jessica Jones spoilers ahead...
He's a pill-popping maniac who doesn't need to get into a woman's head to get her into bed, and Will Simpson is most likely going to be the next big threat Jessica Jones has to deal with - or at least, part of it.
Allow me to explain...
Who is Nuke?
In the Marvel comics, Nuke (real name Frank Simpson) is a super-soldier created by the Weapon Plus project, which also gave birth to the enhanced abilities of Captain America and Wolverine. His face is distinctively emblazoned with a tattoo of the US flag, but unlike Captain he is strictly a villain.
The Simpson of Jessica Jones is a little different, at least on the surface. He has a new first name, Will, and wearing the psychological scars of being "Kilgraved" and coerced into trying to take out Trish, he's filled with remorse.
But while he may at first seem like a good guy, his descent into madness, provoked by those red, white and blue pills provided by the mysterious Dr. Kozlov, slyly sowed the seeds for a different kind of villain to emerge in Season 2.
Dr. Kozlov's pet project
Season 1 was all about Jessica's connection with Kilgrave, her inability to be free of him. His actions were designed to cause her pain. It was personal.
What's interesting about setting up Nuke as a villain is that his motives are so different. He's pretty much a product of Weapon Plus, and as we saw after he popped those red pills - and washed them down with more, instead of the blues prescribed - he's impossible to contain. A killing machine.
But let's not forget that Will was removed from the equation before the first season was done, right after getting his ass kicked by Jessica and Trish in that awesome fight scene...
...after which, Kozlov shows up and has his men extradite Simpson.
How do we know Simpson is going to show up at all in future? Well, why would the writers go the trouble of introducing the Kozlov mystery at all and hinting at his insane back story if it wasn't going to come into play?
Clearly they wouldn't, but that's not to say that Simpson himself is the big bad of Season 2; he's merely a vehicle for whatever operation Kozlov is running...
The IGH Theory
Another mystery Season 1 teased was Trish's investigation into IGH, the organization which covered Jessica's medical bills after the car crash which killed her brother and parents. A Google search revealed that IGH don't actually exist, which of course means that they do exist and would like very much not to be found.
If Jessica's powers were only "activated" by the the car crash (in the flashbacks we see her discover her strength after being adopted by Trish's mother) then it's not much of a stretch to imagine that IGH are responsible, right?
And, besides Simpson, who else do we know that was involved in a series of medical experiments as a child? All roads lead back to Kilgrave, and whilst that could be mere coincidence, his decision to recruit Simpson specifically, of all the officers in the NYPD, seems deliberate.
Whoever IGH are, they seem to be in the business of manipulating accidents and conducting seriously illegal scientific experiments. My guess would be that they are responsible for Weapon Plus, or whatever name that project has been given in Marvel's TV universe, and that Kozlov will have a much bigger role to play in Season 2 - but it's Simpson who'll be our route in.
Jessica's secret weapon
If it sounds like Jessica is well and truly screwed in having to take on Simpson and IGH, she might wanna call in reinforcements - and she wouldn't have to look much further than her own best friend, Trish.
Or is that... Hellcat?
Hellcat's history in the comics goes way back to 1944. She's trained in martial arts by Captain America himself, fights with the Defenders, marries the son of the Devil and spends a period of time trapped in hell, where she develops a series of psychic powers.
The Trish Walker of Jessica Jones has a slightly less absurd backstory, and so far there's no indication of any psychic abilities (as a teenager, for instance, she didn't know Jessica had powers until she saw it with her own eyes)...
However her devotion to martial arts training, combined with the reveal that she used to dream of getting Jessica to don a cape and do the superhero thing, seem to be setting Trish up for her own hero adventure somewhere down the line.
And when it comes to Nuke and the enigmatic IGH, Jessica's going to need all the help she can get.
Credit to Doaly for the brilliant header art.