Ben Foster, Laura Prepon engaged

Actor Ben Foster and actress Laura Prepon have taken their relationship to the next level by getting engaged.

The duo, who have been romantically linked since summer, made their red carpet debut as a couple, at the screening of "Girl on the Train" in New York, reported Aceshowbiz.

The film stars Prepon.

The 36-year-old actress showed big smile as she flashed her diamond ring on red carpet Tuesday, October 4.

Foster, 35, was previously in an on-and-off relationship with Robin Wright before they split for good last year. Prepon's famous exes include Christopher Masterson and Scott Michael Foster.