Civil rights drama The Help has won three prizes at the Screen Actors Guild (SAG) awards, including best cast and best actress for Viola Davis. Another of the film's stars, Octavia Spencer, was named best supporting actress. "Dream big and dream fierce," Davis told the audience at Los Angeles' Shrine Auditorium on Sunday. Silent movie The Artist, tipped for Oscar glory, could only manage one win, a best actor prize for Jean Dujardin. The SAG awards are seen as a key indicator of which films and stars may come out on top at the Oscars. Actors make up the biggest voting group in the Academy of Motion Picture Arts and Sciences, which picks the Oscar recipients. Veteran Christopher Plummer was named best supporting actor for his portrayal of an elderly man who comes out to his family in Beginnners. Like the Golden Globes, the SAG awards also honour television work. Paul Giamatti was named best actor in a TV film or mini-series for his role in Too Big to Fail, a drama about the 2008 financial meltdown. Kate Winslet was named best actress for playing the title role in Mildred Pierce, having won the same award at the Golden Globes earlier this month. The cast of Martin Scorsese's Boardwalk Empire picked up the TV drama ensemble prize, while its star Steve Buscemi was named best male actor in a drama series. Jessica Lange was named best actress in a drama series for her role in American Horror Story. Alec Baldwin won best actor in a comedy series for 30 Rock, while Betty White picked up the best comedy actress prize for Hot in Cleveland. "I think they made a terrible mistake," White joked, adding that the prize belonged to all four female leads in the series. Modern Family won the comedy ensemble prize, while the best stunt award went to Harry Potter and the Deathly Hallows: Part 2. The ceremony also saw Dick Van Dyke present a lifetime achievement award to Mary Tyler Moore, best known for her self-titled sitcom in the 1970s.