Humans series 3 begins filming as Catastrophe's Mark Bonnar joins the cast

Filming is officially under way on the third series of Channel 4's Humans – and we've got our first casting news.

Mark Bonnar (Catastrophe, Apple Tree Yard) will join the sci-fi thriller as Neil Sommer, a charming scientist on a government commission who forms a strong personal connection with Laura (Katherine Parkinson).

Bonnar joins returning regulars Parkinson, Gemma Chan, Tom Goodman-Hill, Emily Berrington, Ivanno Jeremiah and Ruth Bradley.

Colin Morgan is also confirmed to be returning – good news for fans of his character Leo, who ended up apparently brain-dead at the end of series 2.

Set in a parallel present where robots known as Synths are a commonplace accessory, Humans closed its second series with a huge twist – as the entire Synth population was granted sentience.

Picking up one year later, series 3 sees a decimated and oppressed Synth population fighting to survive in a world that hates and fears them.

In a divided Britain, Synths and Humans struggle to broker an uneasy peace, but when fractures within the Synth community itself start to appear, all hope of stability is threatened.

As the synth family, Mia (Chan), Niska (Berrington) and Max (Jeremiah) continue to battle for their right to survival, Joe (Goodman-Hill) Laura (Parkinson) and their children Mattie, Toby and Sophie struggle to come to terms with the cataclysmic events of the last series and their deeply polarised views on the implications of the singularity.

In short: it's man vs. machine... and things are about to go off.

The new series of Humans is written by creators Sam Vincent and Jonathan Brackley, along with Debbie O'Malley, Namsi Khan, Jonathan Harbottle, Melissa Iqbal and Daisy Coulam.

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