The good ship SamJess went up in flames on its first voyage, unfortunately. Jessica Moore died at the end of the Pilot- as my ten-year-old brother asked me, ‘What’s with all the ladies on fire on the ceiling?’
This being Supernatural, Jess went on to put in two more appearances- in What Is And What Should Never Be, as part of Dean’s dream that Sam be happy, and in Free To Be You And Me, when Lucifer appeared to Sam as Jess.
In the Pilot, on discovering that Jess was unaware of Sam’s machete-wielding past, Dean said to Sam, ‘Sooner or later, you’re going to have to face up to who you really are.’ Sam presented a version of himself to Jess that wasn’t exactly a facade- I don’t get the sense that he lied to her, except by omission- but it was certainly cleaned up. The Sam that Jess knew would never be able to torture a demon inside a human body, or slowly behead a vampire with razor wire. Sam is able to act as Dean’s moral compass when Dean gets a little trigger-happy- see Faith, Croatoan, Stairway To Heaven- but Sam only goes off the rails when Dean’s not around, and then he’s worse than anyone.
Sam is aware of this, of the darkness in him. Perhaps the reason he liked being with Jessica was because with her, he didn’t feel like a ‘freak’. And when she died he realised that his past had followed him home; he could never truly be that person.
There are some people in our lives who make us feel like better versions of ourselves. It’s clear that Jess did that for Sam, and Jess became, over the seasons, a kind of symbol of everything Sam had lost- including that person he was when he was with her. I think that’s something a lot of people can relate to.
Why was it, then, that Lucifer appeared as Jess in Free To Be You And Me? At that point, Sam, who blamed himself for the apocalypse, had left Dean to go and become a bartender. One night he woke to find Jess next to him.
The first two times I watched this scene, it didn’t affect me in the slightest. The third time, I was in tears, mostly because of this shot, and the awful vulnerability of it.
The way the scene’s set up, at first you’d think it was a dream sequence- it’d hardly be the first time Sam’s nightmares involved Jess. By then she has acquired the status of a dream to him; another show might have launched into a sex scene at this point, but instead you get the sense that Sam’s worried if he touches Jess she’ll disappear.
Lucifer, by appearing to Sam as the representation of the normalcy he lost, is showing Sam that he can give him anything. Of course, Sam doesn’t back down. By then the Winchesters were probably suspicious of deals that sounded too good, anyway.
But the scene could also be read as Lucifer corrupting what Sam previously thought of as an incorruptible dream. Jess had become sacred to Sam by then; previously she’d never appeared except in the context of the normal world. In WIAWSNB, she practically personified it.
Here, though, she’s Lucifer. Anything can be stained.
And yet despite that ruination, she’s still a beacon. Later in Season Five Sam finds out that Brady, an old schoolfriend of his, was the demon who killed Jess, and it wasn’t just him- many of his friends and teachers were demons too. But Jess was the closest to him, and seemed to be practically the only one who remained unpossessed. (For all we know, Rebecca Warren from Skin was secretly Beelzebub).
Jess was a symbol, but she was more than that; she was one of the first tragedies of the story, a person who was loved and lost, and her death is still referred to once or twice a season. The writers understand her importance- and we know very little about her as a person, but somehow we don’t have to to understand the impact she’s had.
(Note: I was planning on using this screencap. Then I realised whose hand that was.)