Playing a prisoner of war in last year's critically acclaimed Rescue Dawn meant Steve Zahn, until then just another token funny buddy actor, was forced to lose 40 pounds on a diet of vegetables and nuts. As he put it, "I never cheated but it was tough - I'm a meat and potatoes kind of guy." As for Renee Zellweger, earning Oscar noms for both Chicago and Cold Mountain meant losing twice that much: "I lost 80 pounds for those two roles...my tits disappeared so I had to stuff socks into my bra cup!.” And Matt Damon lost 30 to play the nerdy swindler star of 1999's bold-faced name-packed but Oscarless update of The Talented Mr. Ripley.

As a crack addict with a heart of gold in Half Nelson, Ryan Gosling went from Rachel McAdams' cute boyfriend to Oscar nominee by transforming into a gaunt tweaker. But of course, the most frightening metamorphosis of all time has got to be Christian Bale's unrecognizable appearance in The Machinist, a role which earned him just as many rave reviews as it did health problems. As Bale put it, going from 180 pounds to 120 caused "a massive shock to my body because of what I was trying to get it to do...My metabolism had to get back up to speed, because my heart had got used to a whole different way of living for some time."

• FARRELL GOES FROM TRIM TO THIN [The Sun]

Farrell first went to the eastern town of Srebrenica where some 8,000 Muslim men and boys were killed after it fell to Bosnian Serb forces in July 1995.

"I felt sick," Farrell told Reuters after visiting the cemetery for the victims of the massacre, regarded as Europe's worst atrocity since World War Two.

"It is hard to describe how obviously the air and the land has been poisoned by the act of killing 8,000 people in the space of a day. But you really do get the sense of the pain and the loss and I am sad, I really am sad."

Yikes. Indeed, genocide is a bit of a downer, so much so that we're surprised to see the extent to which producers and stars continue to test this market. Particularly Farrell, whose middling run of late (Cassandra's Dream, In Bruges, the perennially shelved Pride and Glory) isn't quite the momentum burst likely to get troubled war stories in front of viewers. We know these stories should be told, but they have to be sold as well. Is there a way to do both that avoids the photo-op cynicism attending Triage and gets us looking forward to these projects for a change?