Secrets and mysteries abound in first trailer for Julian Fellowes' Belgravia

Anne Trenchard has managed to keep a big secret for more than two decades, but it will all start to unravel in Epix’s Belgravia — and EW has an exclusive first look at the trailer.

Premiering April 12, the Julian Fellowes drama introduces Trenchard, played by British actress Tamsin Greig, who decides to defy her husband (Philip Glenister) and share some private information with Lady Brockenhurst (Harriet Walter) that will change their lives forever.

“At the heart of the story, you have a couple who have a secret they’ve agreed to keep,” Greig tells EW of what fans can expect from the series. “The wife has agreed to never speak about it, to honor her husband. Twenty-six years pass, and she comes into contact by incredible coincidence with the woman who is her counterpart within this secret but who does not know the secret. She told her husband she’d never speak about this, but she sees in this woman — to whom she should have no access and has already exposed her own vulnerabilities — and she recognizes a fellow sufferer. She cannot bear to live knowing that someone else is suffering knowing she can do something about it.”

Greig adds, “She breaks that promise to her husband and it’s a catalyst; it’s like dynamite going off in that community and fracturing all of the echelons. And it could destroy, not just her marriage, but also their social standing. She does something extremely foolish because she’s emotionally compelled.”

The consequences of the secret getting out are beyond anything Trenchard can imagine, but could there also be some good? With Downton Abbey creator Fellowes at the helm, viewers can be certain the trip will be full of windy roads, but the journey may be even more fun than the destination.

Watch the trailer above.

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