Silent movie The Artist has triumphed at the Oscars, winning five awards including best picture, best director and best actor for Jean Dujardin. Director Michel Hazanavicius - winning on his first ever nomination - thanked the dog, Uggie, who appears in the film but added: "I don't think he cares". Dujardin said of his character: "If George Valentin could speak, he would say 'Wow! Victorie! Genial! Merci!'" The film also won the Oscars for best original score and best costumes. Martin Scorsese's Hugo also won five Oscars, mainly in technical categories. Meryl Streep won best actress for her portrayal of former British prime minister Margaret Thatcher in The Iron Lady - her 17th Oscar nomination and third Oscar win. She thanked the Academy "for this inexplicably wonderful career". "When they called my name I had this feeling I could hear half of America going: 'Aww no. Not her again'. But, you know, whatever. "I look out here and I see my life before my eyes. My old friends, my new friends. This is such a great honour but the thing that counts the most for me is the friendships… Thank you. All of you, departed and here," she added. Dujardin broke into his native French language in celebration shouting: "Wow, victory!" "Thank you to the Academy. It's funny because in 1929, it wasn't Billy Crystal but Douglas Fairbanks who hosted the first Oscars ceremony. Tickets cost $5 and it lasted 15 minutes. Times have changed." 1929 was the last year that a silent movie won an Oscar. Canadian actor Christopher Plummer became the oldest Oscar winner at 82 by winning best supporting actor. He was widely tipped to win for his portrayal of a father who comes out as a gay man after his wife dies in Beginners. Plummer thanked his real-life wife who, he said, deserved "the Nobel Peace Prize for coming to my rescue every day". The Help's Octavia Spencer won the best supporting actress Oscar and gave an emotional acceptance speech, receiving a standing ovation from the audience. "Thank you Stephen Spielberg for changing my life...oh my God, thank you... I'm freaking out," she told the audience, after struggling up to the stage in a floor-length gown. Best adapted screenplay went to Alexander Payne, Nat Faxon and Jim Rash for The Descendants, starring George Clooney.