The cast of the upcoming Showtime series “The Loudest Voice” used their loudest voices to wish Meryl Streep a happy birthday.

Stars Naomi Watts, Sienna Miller, Seth MacFarlane and Annabelle Wallis shared a bunch of laughs in a video interview as part of the “BUILD Series” on Monday. When a fan in the audience asked which famous person had the biggest impact on their lives, the cast responded with “Meryl.” Learning the movie icon just celebrated her 70th birthday on June 22, Watts, Miller, MacFarlane and Wallis broke out into a rendition of “Happy Birthday” in Streep’s honour.

RELATED: Meryl Streep Turns 70! See All The Birthday Wishes From Her Famous Friends

“The Loudest Voice” chronicles the rise and fall of the late Fox News founder Roger Ailes, who is played by Russell Crowe in the series.

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