As JENNIFER CARPENTER filed papers to divorce costar soon-to-be ex-hubby MICHAEL C. HALL, DEXTER special guest stars JULIA STILES issues denial.

After Hall, 39, and Carpenter, 31,  who play brother and sister on the hit Showtime series announced their split, several  websites alleged Stiles should take the blame for getting too chummy with the Golden Globe-winning actor  —  both in  and out of character.

Stiles, 29, who guest-starred in 10 eps of Dexter‘s fifth season,  denied she was to blame for the nups bust-up.

"I have absolutely nothing to do with the split between Michael and Jennifer," she said. "We are good friends and enjoyed working together. This is a personal matter between them, and we should respect their privacy."

"Although I too prefer to keep my private life, private – I felt compelled to dispel the rumors I was somehow the cause for this matter," she added.

Meanwhile, in the divorce papers filed yesterday by Carpenter, the couple had been separated since August and yet they appeared on the Emmy Awards red carpet seemingly as close as ever.

For those mystified by how that could be – it’s called "acting".