Grin and bear it ... the Turner Prize show

The artist Mark Wallinger is showing a two-and-a-half hour film in which he roamed the national gallery in Berlin at night in a bear suit. It is his bid to win the prestigious £25,000 award.

The work is on show at Tate Liverpool instead of its normal home at Tate Britain because the exhibition has temporarily decamped to help kickstart the Merseyside city's year as a European capital of culture.

Alongside Wallinger's engaging bear, the show incorporates a mesmerising film about an African rope factory, a light installation inspired by a site for miracles and a new work that the London-based artist Mike Nelson was working to the wire last night to complete.

Christoph Grunenberg, Tate Liverpool's director, said they were grateful and excited that Tate Britain had allowed the exhibition to travel north. He urged Londoners: "It's worth travelling for. Come and see the city of Liverpool."

Although the four shortlisted artists worked in diverse media, he said they shared some common themes. "There are certain concerns with history, memory and politics," he said.

Wallinger, 48, who was born in Chigwell, Essex, and lives in London, was also nominated for State Britain, his grand recreation of the Parliament Square anti-war protest.

Although he admitted Sleeper, his bear film, might make some people just smile, it also evoked the history of Germany and the Cold War. Sleeper was another name for a double agent.

The work was shown at the Venice Biennale two years ago but has never been exhibited in Britain. "It just needed to get out," Wallinger said.

The Tate's head of exhibitions Simon Groom said: "The bear is the heraldic symbol of Berlin. In the film, sometimes the animal disappears but when he comes out it's hilarious and forlorn and pathetic and wonderful all at the same time."

Ugandan-born Bhimji, 44, who also lives in London, has travelled India and Africa exploring trade links. She presents new photographs and her rope film. Nathan Coley, 40, from Glasgow, explores social and political systems and their laws. There Will Be No Miracles Here ) one of the works for which he was nominated - was inspired by a French village which was reputedly the site of miracles and magic. In the 17th century, a large notice was erected there which decreed: "There shall be no miracles here, by order of the King."

Mike Nelson, 40, the least overtly political of the nominees, is best known for large-scale architectural installations. After spending the summer creating one of these in New York, he has had just a month to produce a new one in Liverpool.

It includes four identical white cubes into which the viewer peers to find deserts of sand and pricks of light disappearing to infinity thanks to a series of internal mirrors.

Artists, who must be under 50 and from or based in Britain, can make new work or present existing pieces for their Turner Prize exhibition.