First Look: Alexis Bledel's Engagement Ring

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Alexis Bledel debuted her engagement ring on the red carpet Wednesday.

At the Los Angeles premiere of her new TV movie, "Remembering Sunday," the 31-year-old actress showed off a huge octagonal-shaped diamond on what appeared to be a simple platinum band.

"Vincent picked it out," the "Gilmore Girls" star gushed to Us Weekly magazine.

That would be Vincent Kartheiser, 33, who popped the question in March, nearly a year after he and Bledel began dating.

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They met on the set of "Mad Men," where Bledel guest-starred last season as the mentally unstable mistress of Kartheiser's character, Pete Campbell.

After demonstrating his skills in ring selection, Kartheiser plans to lend a hand on wedding planning.

"We're doing it together," Bledel told Us. "We haven't started yet though."

This will be the first marriage for both stars. Kartheiser previously dated actress Rachael Leigh Cook and Bledel dated her "Gilmore Girls" co-star Milo Ventimiglia for more than three years.

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