When is I Know This Much Is True on TV? What’s it about? Who’s in it?

Avengers: Endgame star Mark Ruffalo takes on the dual role of two identical twins

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Spotlight’s Mark Ruffalo is executive producing and starring in HBO’s adaptation of I Know This Much Is True, a bestselling novel about a man whose identical twin has paranoid schizophrenia.


Read on for everything you need to know about the series.

I Know This Much Is True UK release: When is it on TV?

UK viewers will be able to watch the six-part drama on Sky Atlantic and streaming service NOW TV from Monday 11th May 2020 at 9pm. Viewers in the US can watch the show on HBO.

I Know This Much is True review: Is it worth watching?

The limited series currently has a 65 per cent rating on review aggregator Rotten Tomatoes: the site’s critical consensus reads: “Despite strong performances from Mark Ruffalo, I Know This Much is True is relentlessly grim, making it a difficult watch.”

So if you’re a Ruffalo fan, by all means tune in, but gird your loins!

I Know This Much is True trailer

You can watch the official trailer for Sky Atlantic’s UK broadcast of the series below.

I Know This Much is True book: Is the series based on a novel?

Yes, it is based on the second novel by author Wally Lamb, originally published in 1998.

Lamb’s source text was a New York Times #1 bestseller with USA Today calling it “thoughtful” and heart-wrenching”, adding, “It’s hard to read and to stop reading, and impossible to forget.”

I Know This Much Is True cast: Who appears in the series?


Mark Ruffalo (Avengers: Endgame, The Kids Are All Right) plays identical twins Dominick and Thomas Birdsey.

Among his co-stars are Kathryn Hahn (Crossing Jordan) as Dessa Constantine, Dominick’s ex-wife; Academy Award nominee Juliette Lewis as Nedra Frank; Melissa Leo (Mildred Pierce, The Fighter) as Ma; comedian Rosie O’Donnell as Lisa Sheffer, a social worker at the Hatch Forensic Institute; Archie Panjabi (The Good Wife) as Dr. Patel, Thomas’ psychologist; Imogen Poots (Vivarium) as Joy Hanks, Dominick’s live-in girlfriend; and John Procaccino (Rose Red) as Ray Birdsey, Dominick and Thomas’ stepfather.

What is I Know This Much Is True about?

I Know This Much Is True

The drama follows the events of Wally Lamb’s 1998 novel of the same name, about adult identical twins Dominick and Thomas Birdsey, who live in Connecticut.

Thomas has paranoid schizophrenia, and the novel charts the two brothers’ parallel lives, and Dominick struggles to help his brother while also attending therapy and coming to terms with his failed marriage and the death of his infant child.

Described in the show’s official synopsis as “a family saga” and “an epic story of betrayal, sacrifice and forgiveness,” the drama also incorporates flashbacks to the twins’ childhood.


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