Lights, camera, tension! Rachel Bilson wishes Eddie Cibrian would exercise his right to remain silent on and off the set of their new buddy-cop series, Take Two. During a July 2 appearance on Good Morning America, the 45-year-old heartthrob revealed that his co-star, 36, is "grumpy" first thing in the morning and often breaks into fits of laughter during a scene because "she thinks" she’s funny.

"Rachel and Eddie have a love-hate relationship," an insider exclusively told Life & Style. "One minute they’re cracking jokes and the next, they’re at each other’s throats." And anything Eddie says can and will be used against him!

"Rachel and Eddie have amazing chemistry on-screen, but there’s a rivalry brewing beneath the surface," says the insider. "If the show gets picked up for a second season, they’re going to have to find a way to get along."

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