In December 1971, Ernie Wise was in the Guinness Book of Records (The Morecambe and Wise Christmas Show gained an audience of 26 million - about half the population of the United Kingdom ). In December 1992, Ernie Wise was in panto (at the Theatre Royal, Windsor) playing the King in Sleeping Beauty at the Theatre Royal, Windsor. 'The Importance of Being Ernie', tonight's 40 MINUTES (9.50pm BBC2), traces how Wise got from that first Christmas to the second. The popular perception is that Eric Morecambe would have fared much better than his partner has done if Wise had been the first to go. This is bolstered by clips from the old shows in which Morecambe, who died in 1984, teases Wise: 'without me, on your own, you'd be lost'. This documentary, however, contends that they were interdependent; neither could have prospered without the other. Wise, now 67, talks directly - and defiantly - to camera about why he can't just retire gracefully. He recites an anecdote about the old luvvie who can't sing, can't dance and isn't funny. A friend asks him, 'why don't you give up showbusiness?' 'I can't. I'm a star', comes the reply.