Everything You Need to Know Before 'Twin Peaks' Returns

"Who killed Laura Palmer?" was a question that haunted the public consciousness back when Twin Peaks first premiered on April 8, 1990. The show not only changed the landscape of television but entirely redefined how we make, watch, and engage with it. Although the story of Twin Peaks only lasted for two seasons (and an admittedly controversial prequel film), its legacy has endured for much longer, to the point that we're getting a revival of the series.

Thanks to series co-creators David Lynch and Mark Frost, Twin Peaks will return on Sunday for a third season. If you need to refresh your memory on where we last left off with Agent Dale Cooper and the wacky characters of Twin Peaks, we've compiled a small primer to get you caught up. Grab your coffee and donuts, and let's settle in. (Don't worry. The owls can't hear us here.)

Laura Palmer's murder shattered the seemingly quiet façade of the town of Twin Peaks. After her body was discovered, the FBI sent in one of their own to investigate: Dale Cooper. Collaborating with the local police force—among them town sheriff Harry S. Truman (his real name)—Cooper spent time with Laura's family and friends while trying to solve her murder. As it turned out, Laura Palmer hadn't exactly been the innocent high school girl that the town had perceived her to be. Her death wound up serving as the catalyst that unearthed many of the town's most twisted secrets—and some of its deadliest ghosts.

It wasn't one of the unsavory people in Laura's life who was responsible for her death, but someone closer to home: her own father. Possessed by the violent spirit of Killer BOB, Leland Palmer murdered Laura in a fit of rage. In spite of his inability to remember the murder, Leland's gradual mental and physical deterioration ultimately led Agent Cooper to identify him as Laura's killer.

Even after Agent Cooper solved the murder in the 16th episode of the second season (too quickly, according to some fans), there were still plenty of other mysteries in Twin Peaks. The second season largely involved Cooper's exploration into some of the town's most ominous and paranormal places—the Black Lodge and the White Lodge—as well as his complicated relationship with former FBI partner Windom Earle and his romantic pursuit of newcomer Annie Blackburn. The second season finale drives Cooper into dark dimensions after he enters the Black Lodge to save a kidnapped Annie from Earle's clutches. Twin Peaks's original last scene chillingly concludes with Cooper staring into a broken mirror at the reflection of Killer BOB, revealing that his evil doppelgänger was the one to escape the Black Lodge—while Cooper himself still remains trapped there.

For the most part, an impressive number of cast members will be appearing in the revival, albeit with some exceptions—Michael Ontkean, who played Sheriff Truman in the original series, retired from acting in 2011, and Lara Flynn Boyle declined to reprise her role as Donna Hayward. The Twin Peaks revival boasts a number of newcomers like Jim Belushi, Michael Cera, Laura Dern, Robert Kneppar, Matthew Lillard, Trent Reznor, Tim Roth, and Naomi Watts—all in unspecified roles.

Given the ensemble nature of Twin Peaks, it's actually pretty tricky to differentiate between main and supporting characters; the interconnecting plot of the series meant that several storylines could intersect with one another at any point. With that in mind, here are the most likely candidates that the revival will be focused on in relative order of importance, as well as where we last left off with them in the original series.

Agent Dale Cooper (Kyle MacLachlan)
Status: Alive
Quirky yet somehow always by the book (and never without his trusty voice recorder), Cooper's arrival in Twin Peaks is what essentially kicks off the whole plot. While his fate was rendered ambiguous by the finale cliffhanger, Lynch has promised that the revival will elaborate more on what happened to Cooper since the time jump. (Diehard fans may recall that Cooper was intended to be 25 years older in the scene where he dreamed about the iconic "Red Room.")

Audrey Horne (Sherilyn Fenn)
Status: Most likely alive
The resident troublemaker of Twin Peaks and cunning daughter of local businessman Benjamin Horne, Audrey's most intricate plot over the course of the show was a will-they/won't-they dance with none other than Cooper. Although the series never went down that road (partly due to McLachlan's objections over the age difference between the characters), Audrey's role in the revival is said to be "major," leading one to wonder whether she and Cooper will act on those unspoken feelings after all.

Laura Palmer/Maddy Ferguson (Sheryl Lee)
Status: Both dead
Aside from cementing the iconography of the "dead blond girl" in fiction, Laura Palmer's murder was the incitement for many of the most dramatic plots over the course of the original show —including the arrival of her cousin Maddy, who coincidentally bore a striking resemblance to her. Unfortunately, Maddy suffered the same fate as her cousin when she was murdered by her uncle Leland under the influence of the evil BOB.

Leland Palmer (Ray Wise)
Status: Dead
Once outed as the murderer of his daughter Laura, as well as his niece Maddy, the bigger twist was that Leland had been operating under the influence of a demonic presence known as Killer BOB, who had been possessing him since childhood. After confessing to the murders, Leland committed suicide while still under BOB's sway.

Andy Brennan (Harry Goaz) and Lucy Moran (Kimmy Robertson)
Status: Alive
Hapless yet loyal, sheriff's deputy Andy established a reputation as someone who always cries at crime scenes—but his soft side apparently won him the heart of receptionist Lucy. Their relationship was briefly called off, Lucy confessed she was pregnant, and the two eventually reconciled to raise the child together. Hopefully, this is where we'll pick things up again with these two lovebirds.

James Hurley (James Marshall)
Status: Alive
The "secret" boyfriend of Laura Palmer, James initially sought solace in their best friend Donna after Laura's murder. In the second season, he chose to leave Twin Peaks to travel the world and rode off into the sunset on his motorcycle. It can be assumed that his appearance in the revival probably coincides with his returning to town.

Bobby Briggs (Dana Ashbrook)
Status: Alive
Laura's boyfriend at the time of her death, though technically Laura was only using Bobby for his access to drugs. He had a secret affair with married waitress Shelly Johnson, and the two moved in together after her abusive husband Leo was shot. At the end of the series, he proposes marriage to Shelly.

Shelly Johnson (Mädchen Amick)
Status: Alive
A high school dropout caught in a toxic marriage to trucker Leo, Shelly pursued a secret relationship with Bobby Briggs. After Leo was left in a vegetative state following his shooting, Shelly and Bobby proceed to commit insurance fraud under the guise of taking care of him. When Bobby proposes to Shelly, she realizes she can't accept because she's still technically married.

The final scene from the original series

Unfortunately for those who want to look ahead, many of the details are still shrouded in mystery. The original series left more questions behind than it did answers, but given the 18-episode order, there's definitely ample time to wrap up some of the show's biggest loose ends.

Perhaps the biggest question of the entire show revolves around the fate of Agent Cooper. We don't know where Cooper has been for the last 25 years, but Showtime president David Nevins has said the core of the revival will mostly be about "Agent Cooper's odyssey back to Twin Peaks." Similarly, Audrey Horne seems to have made it out of that bank explosion in one piece given that she'll be popping up again.

Other characters suffered a much more unambiguous fate by the conclusion of the second season, including Laura and Leland Palmer. It's unclear whether these deceased characters will be featured merely in flashback or maybe within the interdimensional sphere of the Black Lodge/White Lodge. Either way, their involvement definitely implies an ominous return to form for Twin Peaks.

One of Lynch's most frequent collaborators, Dern has experienced something of a recent career revival on television—most recently in Big Little Lies. As for Twin Peaks, she's been cast in what's being described as a top-secret "pivotal" role.

Speculation has already been swirling over Dern's character, but what many are considering is the possibility that she's playing Agent Cooper's longtime, always-unseen secretary Diane, the woman to whom Cooper dictates all of his tape recordings. (Lynch, Frost, and company have remained infuriatingly mum on the subject.) She's not the only name in the cast being tossed around in regards to the role, but there's something so frustratingly perfect about the idea that it'll almost be a disappointment if Dern plays nearly anyone else.

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Season three of Twin Peaks premieres May 21 on Showtime.