The Hobbit director has expertly trolled Doctor Who fans everywhere with a cheeky video hinting he might direct an episode.

Theories abounded on a special science edition of Q&A, from Einstein's old high-stakes hunches to more recent propositions and pre-occupations. But there was one hypothesis that didn't get a look in, so we are pleased to share it with you here.

Let it go ... and get on those ice skates as King George Square transforms for the Winter Festival, complete with snow machine and ice slide. Plus antiques and pregnancy fairs, thought-provoking theatre and more in Brisbane this weekend.

It's been lavished with praise but the indigenous supernatural thriller is just not that good.

It's personal, says Robert De Niro, as he defends role in autism film festival controversy.