Jennifer Morrison, <EM>The Murder of Princess Diana</EM> Jennifer Morrison, The Murder of Princess Diana

The television gods who control casting have made Jennifer Morrison a very famous young woman. But those who control wardrobe haven't been quite so kind. As Dr. Allison Cameron on House, she gets weekly screen time modeling a lab coat. Now, as she steps into the role of a journalist in Lifetime's TV-movie The Murder of Princess Diana (premiering Saturday, Aug. 25, at 8 PM/ET), she's got the costume blues again. Welcome to Paris 1997, a time of turbulence, tragedy... and high-waisted jeans.

"The high-waisted jeans are really not my thing!" Morrison groans. "It makes me look like I have a belly that I don't!" Of course, they don't make her look like she has a belly at all, because she doesn't. But with blonder hair, a sleeveless blouse and a tote bag, '90s-style Morrison certainly looks a little different waiting inside the marble hallways of the Hôtel de Ville in Dudelange, Luxembourg.

The site has been transformed into the Ritz hotel in Paris, the hub of the action for that tragic night 10 years ago. Morrison waits while director John Strickland sets up a crowd scene out front. A limo pulls up, followed by a swarm of paparazzi on mopeds. Les gendarmes intervene before Princess Diana and Dodi Fayed themselves step out. It's kind of unnerving to see their two look-alikes.

In the scene, hotel security is overwhelmed and Diana (played by French actress Nathalie Brocker, who watched clips of the princess on YouTube to perfect those shy-Di mannerisms) looks petrified. Later the crew will move to Luxembourg city to film the scene in the Alma tunnel. We all know what happened there.

The Murder of Princess Diana is based on Noel Botham's book of the same name, and if you're looking for its angle, check the title. Neither the British secret service nor the paparazzi nor the French police get the full brunt of the blame — "It's not to conclude, it's to explore," says producer Julia Stannard of the film — but we're left in little doubt that Princess Diana's supposedly accidental death was nothing of the sort.

Wading through the intrigue is Morrison's hardheaded, fictional American journalist, Rachel Visco, who finds herself in Paris on August 31, 1997, and suspects foul play. "The deeper she gets into it, the more trouble she's in, so then it becomes this thriller — trying to find the truth is potentially risking her life," Morrison says.

In spite of the controversial subject (and retro makeover), for Morrison it's a welcome chance to step out of the cranky doc's shadow. "The show's called House," she says. "It's a huge show, and it's really great to work with [Hugh Laurie] every day. But to have the challenge of being the one who is the driving force of the story is attractive."

And this is not just any story. Morrison had just graduated high school when she heard about Diana's death, but she understands the fascination: "I think people hung a lot of their identity on the hope they put in her. And to have that taken from you so violently…" But she doesn't necessarily buy the murder theory. "I remember thinking, 'Oh, well, the driver was a bit drunk.' I didn't immediately go to conspiracy."

Morrison, who's been chased by photographers, sympathizes with Diana's life in the spotlight. As extras playing paparazzi jostle behind her, there's an obvious comparison with the interest shown in Morrison's engagement to her House costar Jesse Spencer. But Morrison says she and Spencer stay under the radar — "We're homebodies; DVD and a pizza and beer and we're good." Ask her when the wedding is and she's vague: "In the next year." [The two have since broken off their engagement.]

When she's going to find time for canapé tastings remains a mystery, however, because two weeks after returning from Luxembourg, she's back in L.A. filming House — even though at the end of last season, Cameron, along with most of her coworkers, looked set to leave Princeton-Plainsboro.

Morrison definitely will return, albeit in what she hints might be a different role. "We can only argue with House for so long!" she says. To stir things up, the producers have announced several new cast members. "It's going to open things up for us to come back in a different capacity," Morrison adds. "And then, as far as I know, Jesse and I are going to be in different departments, so we're consulting based on our expertise."

Turns out that Spencer's been here in Luxembourg with her this week. Normally they work together, so visiting each other on set is a new experience for them. "It's been really fun because you have stories to share together," she says. And what might those stories be? "Oh, stuff like, ‘I'm wearing these ridiculous jeans....' "