Although Showtime vaulted into rarefied air with its Emmy win for “Homeland,” the channel continues to offer a spate of shows that clearly have admirers and boast billboard-worthy stars but amount to utility players, failing to reach cable’s elite tier. Two of those, “Nurse Jackie” and “The Borgias,” return April 14, while “The Big C” has been granted the TV equivalent of a dignified death, with four hourlong episodes to conclude the series. A new showrunner hasn’t changed “Jackie” — worth recommending for Edie Falco and not much else — while “Borgias” proves that even papal intrigue and debauchery can grow tiresome.

So if there’s one worth discussing, it’s “The Big C: hereafter” — not because it works, but because the ways in which these episodes fall short illuminate how a promising premise can go wrong, squandering a provocative idea. Even so, credit Showtime with committing to this limited run, offering the audience the one redeeming quality “hereafter” has to offer: Closure.

Starring Laura Linney as a woman who receives a fatal cancer diagnosis, the final season premieres April 29 in its new one-hour format. In theory, the show was going to tackle the terrors of cancer in a darkly comic way, as well as the liberating aspects (with apologies to a certain lyricist) of living like you were dying.

What followed, however, has never consistently approached the more profound aspects of that scenario, and despite Linney’s talents and some terrific guests — including Alan Alda and Brian Dennehy — “The Big C” has lacked the courage of its concept, particularly in this finishing kick, which falls back on the mawkish and sentimental, while leaving Linney’s character to dispense lectures regarding near-death etiquette.

Perhaps most unfortunately, the show had a chance to contemplate death in a non-religious way — namely, how someone who doesn’t possess faith in God’s grace or a glittering afterlife deals with their own mortality. But these hours rely on devices like seeing dead people (where’s that “The Sixth Sense” kid when you need him?), while detouring from the central character’s selfless concern about her family to explore subplots that are, almost without exception, relentlessly ordinary.

It’s a shame, since Linney still delivers compelling moments as the protagonist’s vigor fades, and cancer touches so many lives as to make the situation extremely relatable. Yet the producers too often veer into the absurd — like having the dying wife try to fix up her husband (Oliver Platt) via Internet dating sites while she’s still alive.

On the plus side, those who began the journey a couple seasons ago can at least feel as if they’ve finished the book, which is one of those services pay-cable ought to provide. Otherwise, while it’s not nice to speak ill of the dead, chalk up “Big C’s” final farewell as a big “D” — for disappointment.

The Borgias” remains a serious letdown as well, so grim and joyless it’s hard to derive much satisfaction from seeing Jeremy Irons in a role he was seemingly born to play — the patriarch of the Borgia clan, serving as a lustful, utterly ruthless Pope Alexander. Ultimately, what was cleverly billed as a 15th-century version of “The Sopranos” is at best an impersonation of a quality cable drama, dressed up in fabulous flowing frocks.

The pope and his family spend the initial episodes dealing with an attempt to assassinate him at the end of season two. On top of that, there’s the little matter of the incestuous longing between Cesare (Francois Arnaud) and his sister Lucrezia (Holliday Grainger).

While it’s always nice to escape into exotic settings — and the show’s physical trappings are lavish — there are now plenty of alternatives in this vein, including the promising new Starz hour “Da Vinci’s Demons.”

“We are at war,” Irons hisses in the premiere. That they are, but it’s still mostly a bada-bore.

Finally, Clyde Phillips (“Dexter”) takes over stewardship of “Nurse Jackie,” but his contribution, cast additions (Morris Chestnut, Adam Ferrara, Betty Gilpin) and an altered marital status don’t change the show’s fundamental formula — and whether the newly separated ex-addict nurse can stay sane (or at least sober) amid the usual crises at work and home.

Still, surly kids acting out because their parents are splitting up is a worn-out domestic headache, and the idea that Gilpin’s beautiful resident is a lousy doctor who skates by on her looks is about as stale as it is unenlightened.

“Jackie” remains watchable thanks primarily to Falco, although the best moments are almost invariably dramatic, not humorous. (“I’m not funny,” Falco protested as she claimed her lead-actress Emmy, and while that was too modest, it’s accurate in terms of the show.)

It would be great if these series could enjoy a creative renaissance in their later seasons, but that’s a lot to ask — and as Jackie could doubtless attest, there’s no magic pill for it.

Nurse Jackie

(Series; Showtime, Sun. April 14, 9 p.m.)

Cast: Edie Falco, Eve Best, Merritt Wever, Paul Schulz, Dominic Fumusa, Anna Deavere Smith, Ruby Jerins, Mackenzie Aladjem, Peter Facinelli, Bobby Cannavale, Morris Chestnut, Stephen Wallem, Betty Gilpin, Adam Ferrara.

 Produced by Lionsgate. Executive producers, Clyde Phillips, Tom Straw, Richie Jackson, Caryn Mandabach; co-executive producers, Liz Flahive, Michael Davidoff, Bill Rosenthal, Randall Einhorn; supervising producer, Cindy Caponera; director, Einhorn; writer, Phillips; camera, Bill Coleman; production designer, Ray Kluga; editor, Agnes Challe-Grandits; music, Pat Irwin; casting, Julie Tucker, Ross Meyerson. 30 MIN.

The Borgias

(Series; Showtime, Sun. April 14, 10 p.m.)

Cast: Jeremy Irons, Francois Arnaud, Holliday Grainger, Joanne Whalley, Lotte Verbeek, Sean Harris, Thure Lindhardt, Gina McKee, Peter Sullivan, Julian Bleach, Colm Feore.

Produced by Myriad Pictures, Amblin Television, ImageMovers, Take 5 Prods. and Octagon Films in association with Bell Media. Executive producers, Neil Jordan, Jack Rapke, Darryl Frank, John Weber, Sheila Hockin, James Flynn; producers, Karen Richards, Bill Goddard; director, Karl Skogland; writer, Guy Burt; production designer, Jonathan McKinstry; music, Trevor Morris; costume designer, Gabriella Pescucci; casting, Jina Jay. 60 MIN.

 The Big C: hereafter

(Series; Showtime, Mon. April 29, 10 p.m.)

Cast: Laura Linney, Oliver Platt, John Benjamin Hickey, Gabriel Basso, Gabourey Sidibe, Alan Alda, Isaac Mizrahi, Phyllis Somerville, Brian Dennehy, Dana Ivey.

 Produced by Perkins Street Prods., Farm Kid and Original Film in association with Sony Pictures Television. Executive producers, Jenny Bicks, Darlene Hunt, Laura Linney, Michael Engler, Richard Heus, Vivian Cannon, Neal H. Moritz; producer, Elicia Bessette; director, Engler; writer, Hunt; camera, Michael Caracciolo; production designer, Edward Pisoni; editors, Annette Davey, Michael Ornstein; music, Marcelo Zarvos; casting, Bernard Telsey. 60 MIN.