OK, it's called Twin Peaks, right?  No wonder twins, doubles, doppelgangers, and duplicity are everywhere you look. In fact, the first thing we see in the very first episode are a series of doubles: two ducks in front of the Packard place; a lamp with twin black figurines, and two faces of Josie Packard (Joan Chen) in the mirror.  Everything, and everyone, in Twin Peaks seems to have an exposed side and a hidden side -- it's all part of Lynch's obsession with surfaces and underbellies, facades and the secrets behind them.  So, what appears to be a nice, quiet, little mountain burgh is actually teeming with vice and corruption. The angel-haired prom queen is leading a secret life of drugs and depravity.  The owls are not what they seem -- and neither is anyone else. Because, after all, everybody has secrets...

In Lost Highway (1997) -- an extension (or restatement) of themes in Twin Peaks and especially its 1992 prequel, Twin Peaks: Fire Walk With Me --  a character played by Bill Pullman inexplicably turns into one played by Balthazar Getty halfway through the film.  (The scene in Fire Walk With Me in which Agent Cooper sees himself on a security monitor, standing in the hallway outside, has its parallel in Robert Blake telling Pullman to call home and see if he's there.) The shifting, sometimes bi-polar nature of identity (masks, mirrors, doubles -- and, as always, Lynch's whopping Madonna/whore dynamic), the unknowability of other people ("Open your eyes, James.  You don't even know me," Laura tells James on the night of her murder.  "There are things about me... Even Donna doesn't know me") -- they are the warp and woof of Twin Peaks' the dark, deceptive, and duplicitous universe.

Where do you even begin? The late, blond Laura Palmer has a brunette lookalike cousin (the real good girl to Laura's bad girl) -- although, in Fire Walk With Me, Leland Palmer (Ray Wise) has sex with Teresa Banks (killed a year before Laura, her body, wrapped in plastic, found floating in the river) and tells her she looks "like my Laura."  Madeline first appears as Laura's father Leland is watching a TV soap opera (Invitation to Love, whose title appears on a blue velvet backdrop) involving a suicidal father and his twin daughters, Emerald and Jade, who are played by the same actress. Much later, Windom Earle (Kenneth Walsh) will dress up as a double for The Log Lady (Catherine E. Coulson). The final scene at the Double R Diner in the last episode is a partial re-run of the very first episode at the Double R in the pilot episode, with the late arrival of giggling waitress Heidi and a reprise of some of the same teasing, double-entendre dialogue from Shelley and Bobby. 

There are two Bob/Mike pairs:  Bobby Briggs and his jock friend (Donna Hayward's boyfriend) Mike; and a one-armed man who initially introduces himself as "Mike" (although he's really Phillip Gerard -- a name from The Fugitive) and he's looking for his counterpart Bob -- who turns out to be Killer Bob, whose murderous spirit sometimes inhabits Leland.  Leland himself splits in other ways, too -- as when he undergoes a personality transformation, changing overnight from dark-haired, grief-stricken dad into white-haired, upbeat go-getter. On one level, you could even say that Leland/Bob is a split created in the mind of Laura herself, that Bob is a denial mechanism she creates rather than face what's really been going on at home between her and her father.  Cooper asks a skeptical Truman at one point which is easier to believe -- that Killer Bob would inhabit Leland's body, or that a father would rape and kill his own daughter.  

Eventually, identities in Twin Peaks become so confused -- and, in the second season, systematically reversed, with "good" characters going "bad" and "bad" ones turning "good" -- that when, in Fire Walk With Me, Bobby kills a man in the darkness of the woods and Laura says it's Mike -- Bobby himself isn't quite sure anymore: "Is that Mike?"

The series was cast to emphasize strong physical resemblances between characters.  Leland Palmer and corrupt businessman Benjamin Horne (Richard Beymer) look uncannily alike (and both resemble Agent Cooper to some extent0 -- and they're introduced together in the same shot. So are Dr. Lawrence Jacoby (Russ Tamblyn) and the one-armed man (Al Strobel), both of whom sport grey-flecked beards. Donna (Laura Flynn Boyle) and Audrey (Sherilyn Fenn) -- the "good girl" and "bad girl," who also represent and reflect twin brunette sides of blonde Laura (and who basically switch roles in the second season) look very much alike. And for good reason, as it turns out, since Benjamin Horne is father to both.  (On the asymmetrical side, is there any connection between the one-armed man and Jack with one eye? What about Nadine's eyepatch and her obsession with drapes/blinds? A symptom of her partial vision, perhaps --  her denial of the love between Big Ed and Norma that eventually manifests itself as a regression back to high school as a superhumanly strong teenage cheerleader/wrestler?) 

Related to the idea of doubles and symmetry is the use of palindromes (words or sentences that are spelled the same backwards and forwards).  The backwards-speaking Man From Another Place (Michael J. Anderson) -- "the dwarf," for short -- exclaims: "Wow Bob Wow" -- followed shortly thereafter by a one-word declarative sentence: "Doppelganger."  And Bob himself, who creates doubles by occupying the soul of a human host, is christened with a simple palindrome, a name that is a mirror image of itself. (Remember, too, that the first and last time Bob appears in the series, it is in a mirror -- first in the Palmer living room; then, in the final image of the entire series, above the sink in Agent Cooper's bathroom at the Great Northern.)  

The use of palindromes (and the backwards speech and movement -- then played backwards -- of the figures in Cooper's dream/The Black Lodge) also suggest the way that time runs forwards and backwards through Twin Peaks. In Fire Walk With Me, Cooper visits Laura in a dream before she is murdered.  Annie Blackburne (Heather Graham) appears in Laura's bed, a messenger from the future who tries to help rescue Agent Cooper by planting a message, a clue, in the past: "The good Dale is in the lodge and he can't leave. Write it in your diary."  Unbeknownst to Laura, this is also a warning to those who will survive her that the FBI agent sent to solve the mystery of her own eventual murder will, much later, emerge from The Black Lodge as Bob, while his true self will remain trapped within.  This warning is, no doubt, contained in the pages ripped out of Laura's diary. 

For Cooper, Annie is his "second chance" at love, after his fateful affair with Caroline, the murdered wife of his former partner Windom Earle.  And, in the Lodge, Cooper repeatedly mistakes Annie for Caroline, and vice-versa, as their identities switch back and forth.  His mission now is to save Annie, the way he was not able to save Caroline.  And, for that, he is willing to give up his own soul. Back in Twin Peaks, Cooper awakes ("I wasn't asleep," he says -- perhaps to indicate that what he had taken in Episode 3 for a "dream" was actually a real place, the Black Lodge) and, like a soulless zombie, repeats (twice): "I need to brush my teeth." How chilling that the last words of the series would be Bob (as Cooper) viciously mocking his own initial attempt at impersonating the humanity of Agent Cooper: "How's Annie? How's Annie?"  We now understand why The Giant warned Cooper not to encourage Annie in the Miss Twin Peaks pageant; like detective Jake Gittes [Jack Nicholson] in Roman Polanski's Chinatown (1974)], Cooper is an investigator with flawed vision, who tries to protect and help a woman and winds up inadvertently making sure that she is hurt. [NOTE:  In the original script for Fire Walk With Me (available here), Annie does indeed save Cooper -- getting him out of the Lodge and Bob out of Cooper.] 

Even the diminutive Man From Another Place and the humungous Giant (Carel Struycken) -- though hardly lookalikes -- are presented as doubles of a sort ("One and the same," says The Giant), because they are opposites, representatives of the Black Lodge and the White Lodge, respectively.  

Cousin Maddy's arrival is  prepared for in the previous episode, when the Man From Another Place in Agent Cooper's dream, introduced his cousin who looks "almost exactly" like Laura. He also tells Cooper: "That gum you like is going to come back in style." Doublemint perhaps? (Or maybe Black Jack? The proprietor of One-Eyed Jack's is named Blackie, and the Jack of spades in a deck of cards is, as Audrey's note put it, a Jack with one eye...) Oh, this sort of delicious associative speculation could go on forever -- and would have, if Lynch and Frost had had their way...