Every year during Oscar season, you can always safely guess one thing: Before the awards are presented, critics will complain about how predictable the Oscars are. But while every year seems to have a few obvious results, you do get the occasional shocker. Take the 1996 awards, for example, when Lauren Bacall was expected to be named Best Supporting Actress because, frankly, she was getting old. Instead, young Juliette Binoche's name was announced, which was a problem, because she hadn't even prepared a speech. "I don't know why I got this," she apologized. "I thought Lauren would win." Yes, sometimes the Oscars can surprise. Here are some of the most memorable occasions.

1. Katharine Hepburn (1932-33)

As a young actress, Katharine Hepburn was dubbed "box-office poison," and wasn't well-liked in Hollywood, so just being nominated for Morning Glory was surprising enough. She didn't even show up to the Oscars ceremony, which she might have found entertaining. Host for the night was liberal satirist Will Rogers, joking about Republicans, Hollywood big shots, even Oscars lobbying (predating Jon Stewart's Oscar night banter by 73 years). His rudest joke, however, was reserved for the Best Actress award. Upon opening the envelope, he summoned the other two nominees, May Robson and Diana Wynyard. They rushed up excitedly, assuming that it was a tie (as had happened with the Best Actor prize the previous year). Instead, Rogers thanked them for their performances and announced that the winner was their rival, Katharine Hepburn. (Funny, perhaps"¦ but what a creep!) The stunned crowd replied with a half-hearted applause.

Hollywood later warmed to Hepburn, eventually giving her another three Oscars "“ more than any other actress. Though she never bothered to show up, Hepburn confessed in 1998 that she felt touched by her Oscars. "They gave me their respect and their affection. It was a revelation "“ the generous heart of the industry." Even after her death, she proved that she could still win Oscars, when Cate Blanchett took home a statuette for playing her in The Aviator (2004).

2. Luise Rainer (1937)

When Luise Rainer was nominated as Best Actress for The Good Earth (1937), she didn't even bother to show up to the Oscars, opting to stay home instead. She had won the previous year, and was convinced (like most people) that no actor could ever win consecutive Oscars. Besides, she was up against the revered Greta Garbo, who had never won, for her acclaimed performance in Camille. However, their boss, tycoon Louis B. Mayer, used his considerable power to get an advance peek of the winners' names on the night "“ and found that Rainer had indeed beaten the great Garbo! At the last moment, she was ordered to throw on a gown and rush to the awards ceremony, with no time even to apply her make-up. When her second victory in a row was announced, the audience was somewhat taken aback.

While it was a great honor, it didn't do her much good. Within a year, her career had fizzled. "I have often heard the Academy Award to be a bad omen," she later said. Still, she is the oldest living Oscar winner (at 99), so it's not all bad news.

3. An American in Paris (1951)

The bookies could have made a killing during the 1951 Oscars, when it was assumed that A Streetcar Named Desire would sweep the field. Easily the favorite, it would win four Oscars, including three of the acting awards. A major upset happened, however, when the Best Director award went not to Streetcar director Elia Kazan, but to George Stevens for the long shot A Place in the Sun. Of course, the Best Director usually directs the Best Film. After this shock, all bets were off. It could go either way: A Streetcar Named Desire or A Place in the Sun. When the envelope was opened, at one of the most suspenseful Oscar nights ever, the winner was"¦ An American in Paris.

There was an audible gasp from the audience, followed by loud applause. People who were already leaving suddenly stopped near the exit, wondering if their hearing was all right. Back then, musicals never won the Oscar for Best Film. (The only exception was The Broadway Melody, way back in 1928.) Gene Kelly, the star of An American in Paris, had even been presented with an honorary Oscar that night, which is usually a consolation prize for people who will never win a "real" Oscar. Now his producer, Arthur Freed, was proudly holding one of those statuettes.

4. Grace Kelly (1954)

Judy Garland was a lock for the 1954 Best Actress award for the musical A Star is Born. Not only was it a fine performance, but she was one of Hollywood's best-loved stars. Most of all, this was her great comeback, after years of breakdowns and personal struggles. On the night itself, she was in hospital recovering from her latest drama: the premature birth of her son. A camera crew was at her bedside, she was wired for sound, and her hair and make-up were done for the inevitable announcement.

To everyone's shock, the Oscar instead went to 26-year-old former model Grace Kelly, for The Country Girl. To this day, critics call this one of the strangest decisions in Oscars history. Once again showing her acting prowess, Garland smiled graciously at the news, while being secretly heartbroken. Kelly would retire from acting two years later to become Princess Grace of Monaco.

5. Marisa Tomei (1992)

At the 1992 Oscars, the favorite for best supporting actress was esteemed Australian actress Judy Davis, nominated for Husbands and Wives. Still, she had some fine competition from classical British thespians Joan Plowright, Vanessa Redgrave and Miranda Richardson. With such an outstanding field, many were flabbergasted when Jack Palance opened the envelope and announced that the winner was"¦ cute young Brooklyn-born actress Marisa Tomei, for her funny performance in My Cousin Vinny. To this day, film buffs can't believe it. It was unkindly suggested that, upon opening the envelope, 74-year-old Palance didn't actually read it, but absent-mindedly repeated the name of the last nominee. For the record, many safeguards are in place to ensure that flubs don't become official results.

But how could Tomei have won against such a prestigious group? Well, the Academy is famously patriotic. The British vote would have been split "“ but as the only American nominee, perhaps it should have been surprising if Tomei had not won.

6. Roman Polanski (2002)

Few film directors are as notorious as the French-born, Polish director Roman Polanski. His outspoken opinions about Hollywood have upset many people. His dark and disturbing films, like Repulsion, Rosemary's Baby and Chinatown, are not exactly date movies. Oh, and he has been a fugitive from justice since fleeing the US in 1978 while facing statutory rape charges. So when he was nominated for his movie The Pianist, he was not considered a serious prospect, especially against Martin Scorsese, who (as the Academy was often reminded) still didn't have an Oscar after many years as one of Hollywood's great directors. Scorsese didn't have a lock on the award, however. As Chicago swept the field, things were looking good for Rob Marshall, director of that crowd-pleasing movie. But while Chicago would be named Best Film, it was Polanski who would take the Best Director prize "“ and despite his sordid past, this was greeted with a warm applause. Of course, he couldn't be there to accept it. His friend Harrison Ford accepted it on his behalf.

7. Marlon Brando (1972)

Let's save perhaps the biggest surprise for last. When Brando was announced as the Best Actor winner for The Godfather, it was no surprise. Even though his Don Corleone wasn't really the lead actor (he died somewhere in the middle of the film), he was expected to win for his unforgettable performance. The surprise wasn't in the result, but in the acceptance of his award. Instead of the man himself, a Native American woman in tribal regalia introduced herself as Sacheen Littlefeather. "I'm representing Marlon Brando this evening, and he has asked me to tell you that he very regretfully cannot accept this generous award "“ and the reason for this, being the treatment of American Indians today by the film industry." After she left, to a stunned audience, presenter Clint Eastwood had to follow her. "I don't know if I should present this award on behalf of all the cowboys shot in John Ford westerns over the years," he said.

It was later reported that Littlefeather was actually an actress named Maria Cruz (she has her rebuttal here), and that Brando still received the award, displaying it proudly next to his other Oscar. Still, it goes down one of the great surprises of Oscar night history.