“Dark Shadows,” the much beloved gothic soap opera, marks its 60th anniversary this month.

The show ran but for five years, from 1966-1971, but its afterlife seems eternal.

The entire series is available on DVD, in a gorgeous coffin set, with hours of extras.

Over the years, the serial has been repurposed and rebooted into everything from big-screen films, a primetime series, comic books, paperback novels, a newspaper comic strip, “making-of” tribute books, trading cards, t-shirts, jigsaw puzzles, a ViewMaster set, and even bobbleheads.

And yet even some of the most ardent fans know nothing of the audiobooks.

Big Finish, a United Kingdom company that specializes in audio dramas for cancelled TV series, most notably “Doctor Who,” “Torchwood,” and “Blake’s 7,” reunited original cast members to record new stories from 2006 to 2019.

Such stars as Lara Parker, David Selby, Kathryn Leigh Scott, Jerry Lacy, John Karlen and many more, returned to their iconic roles in fresh tales.

Full disclosure: Big Finish released more than fifty, and I haven’t listened to them all, yet. But I am making my way through the collection, and I have found the stories range from good to mind-blowingly great.

Warning: Some spoilers follow.

The audiobooks explore mysteries of the the wider “Dark Shadows” Universe beyond everyone’s favorite reluctant vampire. Quentin, Angelique, Maggie, Reverend Trask and Tony Peterson, and a grown Amy Jennings headline major stories.

These tales broaden and deepen our understanding of a series you may have watched a half-dozen times. (And should not be confused with the adaptations of Marilyn Ross’ paperback novels narrated by Scott. Those exist in their own universe, one I don’t plan on revisiting. )

Ever wonder what Quentin did when he left Collinwood in 1897? Big Finish has you covered. (“The Skin Walkers,” “London’s Burning,” “The Creeping Fog,” just to get you started.)

How did Angelique manage to zero in on Barnabas after he was freed from his coffin? (“Echoes of Insanity”)

Curious about the final fate of Burke Devlin? Mitchell Ryan returns in “… And Red All Over,” featuring the return of the most hated prop in “Dark Shadows” history.

If you think Josette du Pres Collins suffered before taking a tumble off Widow’s Hill, a certain witch makes her afterlife pure hell. (“Final Judgement,” “The Lost Girl”)

Reverend Gregory Trask knows no peace, not even from the confines of a locked room in the West Wing. His misadventures play out across “The Wicked and the Dead” “The Carrion Queen,” and “The Fall of the House of Trask.”

Selby and his “Falcon Crest” co-star Susan Sullivan prove they still have mad chemistry in “Panic.”

“The Flip Side” terrorizes Carolyn Stoddard with a question the original series couldn’t be bothered with: Just who was the victim of that hit-and-run that Roger Collins committed and framed Burke for?

A young Judith Collins (voiced by “Buffy the Vampire Slayer” star Amber Benson) discovers love and worse in the walled-up ballroom of Collilnwood in “Dress Me in Dark Dreams.” Of course, Collinwood has a cursed ballroom! It seems obvious, doesn’t it?

Most of these tales run about 70 minutes and spotlight a few characters, but a handful are more ambitious.

“Bloodlust” runs 13 episodes for about eight hours and features about 20 main characters. Like the original series, some of the writing is inexplicable. Angelique’s idea of getting even with a man stupid enough to threaten her is to age the man’s infant into a full-grown man.

As revenge spells go, that’s pretty random.

Yet the payoff is perfection as the mother of that child happens to be a grown Amy Jennings (voiced by Stephanie Ellyne), forcing Quentin to do something he never did in the series: Out himself as her great-grandfather and reveal that Amy’s first-born is now cursed to howl at the moon.

I could have had two hours of these two bickering over family history. Amy is so not thrilled to discover she’s a Collins.

The story centers Maggie Evans as something she never was in the series: The antagonist. As the leader of an increasingly unhinged vigilante group in Collinsport, Maggie threatens the existence of Quentin, Barnabas, and Angelique.

Whatever its plotting hiccups, the penultimate episode thrills in ways unexpected: Maggie faces off against Angelique. It’s two angry, broken women for the entire episode, laying bare their grievances, sharing all their secrets. It’s the best work Parker and Scott have ever done in “Dark Shadows,” if not their entire careers.

My biggest gripe here might be the cover of the excellent Robert Cobert theme music, here rendered into something weak and annoying. Why mess with perfection?

If you are a true “Shadows” nerd, Big Finish has more surprises.

Ever wondered how the first Reverend Trask encountered the supernatural? Lacy narrates a story he wrote, “Trask the Exorcist,” part of “Echoes of the Past.”

Selby named his son after Jamison Collins, and Jamison Selby stars as a grown Jamison in “A Collinwood Christmas.”

Young David’s two besties, Amy and Hallie Stokes, never crossed paths in the original series, but they do here. Kathleen Cody returns as Hallie in “Carriage of the Damned” and “Tainted Love” opposite Ellyne’s Amy. Hallie has not grown up well and is traumatized by her time at Collinwood.

Still, even more fan fun, the original Amy, Denise Nickerson, pops up as a new character in “Carriage of the Damned,” interacting with Hallie.

There are at least two books that belong in every “Shadows” fan collection:

“The Crimson Pearl,” released to coincide with the show’s 45th anniversary, focuses on a cursed bauble that is passed down through the generations and features by appearances from the likes of such unexpected characters as Millicent Collins, Rachel Drummond, and parallel time’s Alexis Stokes.

It’s a fun ride through Collins’ history with a satisfying payoff.

“Blood & Fire,” released for the show’s 50th, runs about two and a half-hours and finds Angelique sent back in time to 1767 to destroy the Collins line. But she has second thoughts when she meets a young, innocent Laura Murdoch (voiced by the prime-time revival’s Joanna Going). Fate has a way of dooming both women.

We’ve lost so many of the players in recent years: Parker, Karlen, Ryan, Nickerson, Chris Pennock. They live on in these dramas.

For me, the Big Finish audiobooks are every bit as canon as the series, rich enhancements to the show’s legend. If you haven’t listened, you’ve missed half the story.