The CBS series "Ghost Whisperer" certainly falls into this category. It has helped CBS remain competitive on Friday nights, it continues to draw a faithful fan base and despite some cast changes, the show remains creatively strong.

The show's premise is pretty simple. Jennifer Love Hewitt plays "Melinda Gordon," a woman who can see and communicate with people who have not "crossed over." She marries Jim Clancy (David Conrad) in the premiere episode, and her relationship with her husband helps define and expand her connection to these ghosts.

Over the period of four seasons, there have been some cast changes and a couple of long-running story arcs that focused on the dark side of the afterlife. But throughout the series, the one constant has been the bond between Melinda and Jim.

But more changes are coming to the show, and it's going to be interesting to see how fans react to a new three-episode arc, which premieres tonight.

For months, rumors have been swirling that David Conrad (who plays Jim, Melinda's husband) will be killed off this season. Producers have been coy about the changes, simply stating that Conrad will not be leaving the show.

It's tough to write much about these episodes without spoiling too much of the story arc, although I'm not giving away much to say that things do not end well for Jim in tonight's episode (entitled "Imaginary Friends And Enemies"). In fact, the promo CBS is airing for the episode gives a pretty good indication of what is going to happen.

But the cliffhanger from tonight plays out across at least the next two weeks, and although I suspect that many fans won't be happy with the storyline, it is an imaginative twist in the show. It's a change that seems very believable in the context of the series so far, and it gives the under-appreciated Jennifer Love Hewitt the chance to show off acting chops.

It also gives the viewers a lot to think about. At what point does holding on to something or someone cost more to your heart and soul than you can afford to pay? If you believe in heaven, then do you also have to believe that every event has a purpose, even if you don't see it at the time? Do you sometimes just have to turn your life over to a higher power, and trust things will work out in the end?

Regardless of what fans think of the episodes, they are some of the best episodes of the series. Even though you can probably guess some of what is going to happen, there are some real unexpected twists and some connections between characters that I didn't see coming.

Even if you're not a regular fan of the show, it's well worth tuning in tonight. You don't have to be a fan to follow the action, and it's a chance to see some really good television. With all the jokes about her bustline, it's easy to forget that Jennifer Love Hewitt is a good actress. And while David Conrad hasn't always had a lot to do in some episodes, tonight's hour gives him the chance remind viewers "Ghost Whisperer" has succeeded in part because of the strength of its ensemble.

"Ghost Whisperer" airs Friday nights on CBS.