Maris Crane is introduced (offscreen) as Niles Crane's first wife, although they divorce later in the series. Viewers never see the character, but are inclined to create their own image of her form, especially using the vivid explanations given by anyone who has met her - above all her husband. The true source of Maris' family fortune is only discovered by Niles during the divorce proceedings.
Our first impression of Maris Crane is when Niles explains to Frasier about how their gardener, Yoshi, angrily demolished a topiary. Her reaction to this violent occurrence was expressionless, but she was evidently mortified. When discussing how Martin's condition makes him practically unable to live alone, Niles points out to Frasier, that having him over at their house wouldn't be good because he (Martin) doesn't like her (Maris). Frasier tries to compliment her by saying that she's "like the sun, except without the warmth". Later, Niles refers to Maris as being five years older than he is. (The Good Son (Pilot))
During an attempt at preparing for dinner, Maris collapsed in her half-slip and sighed, revealing to Niles that dinner was not to be. (Dinner At Eight)
During the party, thrown for special guest and well-known artist Martha Paxton, Maris was mentioned by Niles as being asleep under the covers of Frasier's bed after she became exhausted from pressure to be interesting to other guests at the party. He inadvertently allowed a guest to throw a coat on that same bed. Later in the episode, Daphne helped to recover her lost earring. (The Crucible)
Maris is known to have a sexual side. After watching Basic Instinct, Niles explained that they pushed their beds together that night. He also mentioned that their beds were across the hall from each other, implying that their marriage wasn't mutual. (Selling Out)
Even with her problems, Maris was very active. Niles explained that she was taking part in the show, Cats. He hoped it would be more successful than the unlikely 'The Sound of Drums'. At the end of the episode, Niles was sorry to announce that she had been kicked out of the cast after forgetting the words to 'Memory'. (Oops)
Frasier was obviously noticing Niles' attraction to Daphne and guessed it had something to do with his relationship with Maris. Niles agrees and explains that there's a lack of love. Frasier suggests role-playing. This idea evidently doesn't work as Niles arrives in Frasier's apartment dressed in a Pirates costume. Niles tells them that Maris had left for Arizona after the shock.
For her return, Niles decides on making a romantic dinner to make up and takes Daphne to make the food. We are first revealed to the sights of their glamorous house. Niles explains that it was all hers, implying that she was rich. They met when their hands touched outside her gate and a spark opened the gates before them, as if a sign. They married three years later. Daphne notices a glockenspiel, which Niles points out to be their honeymoon sentiment from Zurich.
Ironically, Maris is unable to return home because of the steadily brewing storm. When staying the night, Daphne is forced to wear a white gown, saying that Maris' clothes were all too small for her. (A Midwinter Night's Dream)
When preparing for the Seabee Award ceremony for Frasier, Niles explains that she caught a glimpse of herself in the mirror. Even though the end of this sentence is cut off, it isn't hard to understand her absence. (And The Whimper Is...)
Niles obviously has feelings for her because he bought her an emerald necklace. In the same episode, he explained that Maris was very kind (a lie), and apparently gave all her old cocktail dresses to the homeless. (Give Him The Chair)
Maris finally leaves Niles' life, seemingly forever, in the season 11 story arc where she kills her Argentinian polo-playing lover, is imprisoned, and escapes to her family's private island from which she can't be extradited, effectively stranding her for life. Niles does, however, manage to stand up to her directly for the first time in their acquaintance just before she flees.
- [Through a keyhole]
Roz: I see her coat on a hat rack
Frasier: Look closer, is the hat rack moving?
Roz: Oh, my god [it is]!
- [On a saucy film Niles and Maris watched together]
Niles: I don't mind telling you we pushed our beds together that night! And that is no mean feat: her room, as you know, is across the hall.
- [About dinner reservations]
Frasier: Will Maris be joining us?
Niles: Sadly, no. She had a bad experience there one Christmas Eve. The Italian soccer team was at the next table, Maris announced that she was in the mood for a goose, and, perhaps inevitably, tragedy ensued.
Frasier: I thought Maris was joining us?
Niles: Oh, no. I'm afraid Maris is having one of her episodes. In the middle of dressing for the evening, she suddenly slumped down on the edge of the bed in her half-slip and sighed. Of course, I knew then and there that dinner was not to be.
- [During an episode of extreme sexual frustration]
Niles: Right now Maris is slipping out of her frilly underthings and into a non-fat milkbath.
- [On Maris not being able to have pets]
Niles: She distrusts anything that loves her unconditionally.
- [At a banquet]
Niles: Oh look, Maris has cornered Mrs Beaumont, she's been wanting to discuss getting on the museum board for months. Oh, Mrs Beaumont thinks to escape with the old freshen-the-drink ploy, she obviously has no idea who she's dealing with. That's right Maris, chug that sherry, on with the chase! It's Mrs Beaumont and Maris, coming around the ice sculpture, Mrs Beaumont and Maris, Mrs Beaumont and Maris, and yes, they meet again! (Roz, Frasier, Niles, Martin, and Father Mike all clap.)
- [Niles finally gets through to Maris on the phone during a citywide blackout]
Hello, Maris. Thank God I got you. Listen, darling, there is no need to panic. The most important thing is to stay calm... About the blackout. Maris? Take off your slumber mask. [Niles suddenly holds the phone away from his ear] Ooh! No darling, darling, don't panic. Honey, no, honey, hon, ho- ho- h... [turns the phone off and puts it back in his pocket] She's fine.
- [Niles, Roz and Fraiser are watching out the window of Cafe Nervosa]
Niles: Look, you see that rotund woman coming out of 'Chock Full o' Donuts'? Watch. Before she gets to her car, she'll finish that bear claw, and then go back in - this is her third time.
Roz: You called us over to show us that? It's rude.
Frasier: It's childish. [He and Roz walk away]
Niles: It's Maris! [They come back]
- [Niles is watching Maris walk into a deli after Chock Full o' Donuts]
Niles: Oh, the manager just took the three-foot salami out of the window.
- [At Frasier's peephole]
Niles: It's Maris! ... at least I think it is, you need a bigger peephole.
- [When Maris takes refuge on a bed at Frasier's during his party]
Niles: I got Maris into Dad's bedroom, but I had to butter her up a bit.
Frasier: I was afraid that narrow doorway might pose a problem.
- Niles: She exhausts easily under the pressure to be interesting.
Although she is mentioned a lot of times throughout the series, her actual face was never revealed. This is similar to the character of Norm Peterson's wife Vera in "Cheers", the prelude to "Frasier", and other sitcom characters such as Peggy Bundy's mom in "Married... With Children", Dorothy Zbornak's brother (and also Sophia Petrillo's son) Phil in "Golden Girls", or even Columbo's never seen wife. She is even referenced in David Hyde-Pierce's guest appearance on The Simpsons' Brother from Another Series.