There is — let's be clear up front — virtually no such thing as a Christian series on network TV. Nor, really, has there been for a long time, if ever. Sure, there've been shows which portrayed Christianity and Christians in a positive light. But even Touched by an Angel rarely mentioned Jesus by name, presenting instead a generic "God loves you" message. None of this comes as a surprise: Hollywood is, well, Hollywood.

But what may be surprising is how often Christian themes are popping up on TV. It's surprised me, anyway. Or it used to.

I first started to notice it a few years ago on a cop show called The District, where several characters were churchgoers, and one devout believer (a young male detective) practiced chastity before marriage. A number of episodes focused heavily on themes of faith, and in those shows characters displayed some scriptural literacy. (They quoted verses other than the famous handful everyone knows — the sort you'd only know if you actually spent some time with the Bible.)

Since then I've been pleasantly surprised to see similar things in other series, on a recurring basis. Sometimes the shows have been theologically off-base, or shallow, or marred by mixed messages (e.g., "Christian" characters who sleep with someone not their spouse, apparently guilt-free). But it's a far cry from the days when believers on TV were portrayed chiefly as self-righteous hypocrites, fanatics and fools.

There's reason to believe Christian themes are resonating with viewers — even when those themes aren't explicitly labeled as Christian.

Case in point: One of the biggest hits in many years, Lost. The series — about plane-crash survivors on a mysterious island where weird, unexplained things keep happening — gets most of its media buzz for its suspense and its eerie, sci-fi elements. And to be sure, that's captivating stuff which has helped generate a cult following. But it doesn't wholly account for its mainstream popularity (20 million-plus viewers a week). The show owes its strongest drama to stories of people haunted by the deeds (often misdeeds) of their pasts. These stories, told in weekly flashbacks, are usually tales of sin and guilt, and they're used to set up the characters' ongoing quests for redemption.

Take Kate, a fugitive from the law. She may not be at fault for her original offense (which hasn't been revealed), but she developed a deceptive and conniving side and, in a reckless escape attempt, got her childhood sweetheart killed. Tormented by that knowledge, she often tries to do what's right; she's brave and puts herself in danger to help someone who needs it. But at times she still lapses into lies and manipulation, most of which she finds a way to rationalize. Old habits die hard.

Take Sawyer, the sleazy con man. He started out as a victim, orphaned when his mother had a fling with a previous sleazy con man, leading his father to kill her, then commit suicide. But on his own, Sawyer grew into a mirror image of the man who victimized his family. Filled with self-loathing, he acts his worst and goes out of his way to provoke hostility and contempt, which is all he thinks he deserves. Slowly and sporadically, his conscience is moving him to reform, but he's got a long way to go.

Take Charlie, the washed-up rock star. Once a pious churchgoer who went to confession and feared corruption by the music world's temptations, he succumbed to the lure of promiscuity and drugs, and later fell to using women in schemes to raise money for his addiction. Clean and sober at the moment, he's trying to care for a fellow crash survivor (Claire) who spent most of the first season pregnant and now has a newborn to raise. But he's discovered a new stash of drugs in the wreckage of another plane, so temptation is still staring him in the face.

Take — well, pretty much all the characters, to one degree or another. Jack is a doctor who carries the weight of the world and takes every failure hard, including his broken relationship with his just-deceased dad. Michael is an absentee father trying to build a relationship with a resentful 10-year-old son. Jin and Sun are a Korean couple whose marriage deteriorated through secrets, lies and professional ambition. Sayid is a former Iraqi military officer trying to live down a history that includes torturing prisoners. They're all dealing with guilt, and while they're not all equally culpable, none is entirely innocent. And that's by design, according to series co-creator Damon Lindelof. "It feels like these people have sort of sinned in their lives before, and now, they're in an environment where they can't talk to the people that they need to talk to," he says. "They can't close the doors that they need to close."

But if sin is an ongoing element on Lost, so is the supernatural. Strange forces are at work on the island — sometimes to dark purposes, but other times to benevolent ends.

The best example is the character of John Locke. (Yes, history buffs, that's his name). Previously, he was crippled, physically (confined to a wheelchair) and emotionally (callously exploited by a birth father he met late in life). On the island, he was miraculously healed. Now he's developed into a wise spiritual leader and mentor, displaying a measure of peace that contrasts strikingly with everyone else's anxieties. (One character marvels to him that "I don't think I've ever seen you angry.")

Not that Locke's life is easy. He clashes at times with Jack the doctor, and he explains their differences of opinion by telling Jack "you're a man of science; I'm a man of faith." Locke doesn't mean it as a boast; he's only appealing to his comrade to recognize that some supernatural agent is guiding events in ways mere humans cannot grasp. (Jack, for his part, will be taught "to let go of some really strict science dogma, given the situation in which he's living," says the actor who plays him, Matthew Fox.)

Of course, we don't know just what Locke's placing his faith in, nor for that matter does Locke know: He speaks broadly of doing what "the island" wants, but doesn't know who (or Who) is behind the island. Other characters, however, have more definite ideas. Charlie, the believer who's lost his way, finds himself seeking counsel and absolution from a kindly and faithful Christian woman named Rose. She, in turn, invites him to join her in prayer: ("Heavenly Father, we thank you. We thank you for bringing us together tonight, and we ask that you show Charlie the path.... ")

All this, to be sure, falls far short of making Lost a Christian show.

For one thing, there's some sexual content, to say nothing of folk who spend time in various states of undress. Interestingly, sexual activity is often portrayed negatively, reflecting the vices of characters' previous lives, but alas, not always: At times it's just gratuitous. Moreover, Lindelof says producers have contemplated turning one of the characters gay. That might not happen, since it would be creatively senseless (all the characters have been established as straight) and would alienate a sizable chunk of the audience. Yet the fact that producers are thinking about it anyway should tell us something.

For another thing, the series is — after all — a sci-fi series, and supernatural events go with the territory. True, Lindelof has said it intentionally employs biblical allusions, including a first season that's supposed to take 40 days and 40 nights. (At the start of the second season, the homeless survivors find shelter, of a sort.) But Lost also contains a wide range of literary and cultural references. Maybe there's a Christian writer or two in the mix, but it seems likely that Scripture is just one of many sources the writers draw upon to tell a compelling story.

And above all, Lost hasn't presented a Christian understanding of redemption. Many characters are trying to make amends for their offenses and become better people. No one's saying "my only righteousness is the righteousness of Christ." Not that you'd expect it on TV, but the distinction is crucial. The world is full of people who feel bad about who they are and what they've done; who want forgiveness and personal transformation. But the forgiveness they want comes from other people, and the transformation they want comes from themselves. They want to believe they can become good people who don't need to repent all the time. They don't want to say daily, with Martin Luther, "we are beggars." In short, they want things on their terms, not Christ's.

Yet if Lost doesn't amount to an evangelism story, it does work as a sort of pre-evangelism — whatever the writers' intentions may be.

That's because scriptural themes do make compelling, even irresistible, stories. All of us know certain things deep down, even when we try to pretend otherwise. We sense that the world is a vast, wondrous place, with mysteries and a Maker beyond our comprehension. We know what it's like to be lost souls in need of redemption. We know the consciousness of sin, the experience of guilt and the longing to be cleansed of its stain. We know the desire to start over again, refreshed and healed. These are the basic realities of our lives, and they're bound to have a powerful pull on us all. There's no getting away from them.

We Christians can just be thankful that we have the most compelling story of all. The one where the lost souls are found, and the lame are forever healed.