The mystery deepens as FBI and other law enforcement – played by David Lynch, David Duchovny, Miguel Ferrer and others – get involved.

[Editor’s Note: The following contains spoilers from “Twin Peaks: The Return” episodes as they’re released weekly.]

With a huge cast and 25 years intervening between the original “Twin Peaks” and “The Return” on Showtime, familiar faces may not be all that familiar anymore. While Parts 1 and 2 reintroduced many of the main returning characters, whom you can reference here, the next two episodes that aired Sunday trickled in a few more.

READ MORE: ‘Twin Peaks’ Episode 4 Is a Gift Filled With Answers — And a Warning About Wanting More

Here’s a breakdown of who’s who from the original series that showed up in Episodes 3 and 4:

Major Garland Briggs (Don S. Davis)

Showtime

The Air Force officer had been part of a classified operation that was investigating the White Lodge and was the father of Bobby Briggs (see below). Although actor Don S. Davis died in 2008, an image of Briggs’ floating head is seen while Agent Cooper is in space. As the head, superimposed over the space landscape, floats by, it says, “Blue Rose,” an FBI designation for certain supernatural cases.

American Girl (Phoebe Augustine)

Showtime

Eagle-eyed fans will recognized Phoebe Augustine, who played Ronette Pulaski in the original series, as this woman in the Purple Room who is only credited as “American Girl.” Ronette had endured much of the hardship that Laura Palmer did and was even present when Laura was murdered. It’s not clear if American Girl is supposed to be Ronette or another character entirely. She only urged Cooper to hurry and go since her mother was coming, whatever that means.

Dougie Jones (Kyle MacLachlan)

Showtime

Just when you think the show has maxed out how many roles MacLachlan can play in one show, never second-guess David Lynch. Dougie appears to be a shrubbier, grey-haired version of Cooper but one who lives a suburban life with a lovely wife (Naomi Watts) and kid (Pierce Gagnon) and mistress, whom he meets in houses on the market that still have not been sold. We never met him in the original series, but his resemblance to Cooper or the Doppelgänger is no mistake. From what we can gather after he was magically placed in the Black Lodge is that he is a fake, a decoy Cooper needed because if real Cooper were to leave, the Doppelgänger had to take his place. With lookalike Dougie though, both Cooper and the Doppelgänger are currently in the real world simultaneously, which could have some serious consequences. Dougie poofed away to become a gold bead in the Red Room, leaving behind the Owl Cave Ring, which the One-Armed Man placed on a table.

Agent Albert Rosenfield (Miguel Ferrer)

Showtime

Rosenfield is a complex and conflicted man who had assisted with Cooper’s investigation into the Laura Palmer case in the original series and is still an active FBI agent 25 years later. Meeting up with the man that the agency believes to be Cooper (but is in fact his Doppelgänger), Rosenfield feels something is off and reveals to Agent Cole some information about Phillip Jeffries (see below). Actor Miguel Ferrer died in January 2017, after he had finished shooting his scenes for the series.

READ MORE: ‘Twin Peaks’ Episodes 3 and 4 Review: More Than Ever, David Lynch Is Still Screwing With Us

Agent Gordon Cole (David Lynch)

The FBI Deputy Director appeared in the original series as Agent Cooper’s superior after he had been shot. He took a shine to diner waitress Shelly Johnson (Madchen Amick) and the cherry pie there. Twenty-five years later, he’s still active with the FBI and got called to South Dakota to speak to Cooper (actually the Doppelgänger) who was being detained after a car accident. Later, as he speaks to Rosenfield, he agrees that this whole situation with Cooper is a blue rose case that “doesn’t get any bluer.”

Denise Bryson (David Duchovny)

Showtime

Formerly a Drug Enforcement Administration special agent known as Dennis, Bryson realized she identified as a woman after an undercover operation. During the intervening 25 years, Denise Bryson is now the FBI’s Chief of Staff and approved Agent Cole’s operation to speak to the newly rediscovered Cooper (who was actually the Doppelgänger).

Bobby Briggs (Dana Ashbrook)

Showtime

In the original series, Bobby was a rebellious teenager who was dating Laura Palmer, which is why he was an early suspect in her murder – especially when it was revealed that she had been cheating on him with another guy. Bobby had been cheating on her, however, with Shelly Johnson, and by the end of the series realized he loved her. After 25 years, it’s revealed that Briggs had become a deputy in the Twin Peaks Sheriff’s Department and was shocked, to put it mildly, when he realized that Laura Palmer’s case was being investigated in regards to Agent Cooper. He also mentions that Cooper was the last person to see his dad alive.

Agent Phillip Jeffries (David Bowie)

Moviestore/REX/Shutterstock

Technically, we didn’t see this agent again but Agent Rosenfield did mention that sometime in the intervening 25 years, Jeffries had called him to authorize info that Cooper needed urgently. But a week after that intel was released, their man in Colombia was killed. David Bowie was supposed to reprise his role before his death in January 2016.

For a refresher on the familiar faces seen in Episodes 1 & 2, read here.

Check back next week for Part 5.

“Twin Peaks” airs on Sundays at 9 p.m. on Showtime.

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