There's nothing like the final season of a quality TV drama. Unencumbered by the need to keep the show running for years on end, a show's creative team finally has access to every card in the deck. Think of the bloodbath in The Sopranos' penultimate episode, or the net closing around Vic Mackey in the final hours of The Shield.

We're now within a stone's throw of the final moments of two major TV dramas: Showtime's Dexter and AMC's Breaking Bad. It's exciting because all bets are truly off; anything can happen, and every character is expendable.

At least, that's how it would be, if not for the news that both Dexter and Breaking Bad are likely candidates for spin-offs after their series finales have aired. For the past year, Breaking Bad showrunner Vince Gilligan has been floating the possibility of a spin-off centered on Bob Odernkirk's slimy lawyer Saul Goodman. (The Breaking Bad spin-off "is not a done deal yet, but it's definitely something we're full speed ahead on trying to get going," Gilligan said in a recent interview with The Wrap.) And last week, Showtime president David Nevins offered similarly strong hints about a Dexter spin-off. When asked if the network was still considering spinning off the drama, he said, "Of course. We just signed a deal with [Dexter showrunner] Scott Buck. Draw your conclusions."

The spin-off has been a part of the television landscape since 1955, when Jackie Gleason spun his popular Ralph Kramden character from the variety series Cavalcade of Stars into The Honeymooners. Since then, some of the most durable and popular sitcoms of all time have been spin-offs from other popular series, including The Jeffersons (which spun off from All in the Family), Laverne & Shirley (which spun off from Happy Days), and Fraiser (which spun off from Cheers). Done well, a spin-off can flesh out a character's world and keep fans hooked. Done poorly… well, remember Joey?

The idea of spinning off one of TV's modern, serialized "prestige dramas" is a relatively new one — and one with far greater implications than your average sitcom spin-off. It's not quite fair to say that other prestige shows haven't attempted to expand their universes through alternate channels (including a couple of awful Playstation 2 games based on The Sopranos and The Shield). But it's also safe to say no one expected Friends to end with a massive gun battle that left most of its characters dead. Is there any real potential in a spin-off of a tightly serialized drama — and will the existence of a spin-off affect the way we think about and talk about these shows in the future?

Dexter — which spends most of its its time on the witty monologue running through its protagonist's head — seems like a particularly inapt choice for a spin-off. Dexter is Dexter — it's right there in the title — and it's hard to imagine the same audience tuning in for a show like Debra, or Masuka, or Batista. In eight seasons, the show has failed to introduce a character that's even half as interesting as its lead, and barring an eleventh-hour twist — like, say, Debra deciding she'd also like to start killing serial killers — Dexter doesn't seem to have much inherent spin-off potential.

But the much-discussed Breaking Bad spin-off is a trickier beast. Breaking Bad is one of the tightest shows on television. While it boasts an incredible supporting cast of characters, each of them is just a satellite in the orbit of Walter White, whose journey from Mr. Chips to Scarface has been the stated goal of the series from the very beginning. Gilligan has been very careful to make sure that the existence of a possible Saul Goodman spin-off doesn't tip Breaking Bad's final hand. ("You never know, when the dust settles at the end of our final eight episodes, where everybody's gonna be and who's gonna be left standing," said Gilligan. "I can't even say for sure that it could be a sequel. It may be, it may not.")

Gilligan's pitch for a Saul Goodman shows seems deliberately divorced from most of the things we know about Breaking Bad. Gilligan hasn't even decided if it would be an hour-long drama that "fits more snugly in with the Breaking Bad universe" or a show that's "a little more traditionally half-hour comedic." "I like the idea of a lawyer show in which the main lawyer will do anything it takes to stay out of a court of law," said Gilligan in a 2012 interview with Indiewire. "He'll settle on the courthouse steps, whatever it takes to stay out of the courtroom. That would be fun — I would like that."

That does sound fun. I'd love to watch a show about Bob Odenkirk playing a smarmy lawyer who's more or less identical to Saul Goodman. I'd love to see AMC roll the dice on something that's a little lighter in tone than Mad Men, The Killing, Hell on Wheels, and the upcoming Low Winter Sun. I'd love to see Vince Gilligan running another show — any other show — now that Breaking Bad is coming to an end.

But even if we have every reason in the world to put faith in Gilligan and his creative team, it's hard not to be nervous about the chance that something in the Saul Goodman spin-off will take away from the way we experience Breaking Bad — which is, remember, about to premiere what AMC has aggressively promoted as "The Final Eight Episodes." No one likes an asterisk in a record book, and no one wants a misguided footnote to Breaking Bad's otherwise unimpeachable run. In a way, it's a possibility that's perfect for Breaking Bad; there's just as much risk here as there is opportunity. But we won't know until Breaking Bad completes its final run whether it's worth picking up that phone and calling Saul again.