The cast of The Staircase compared to their real-life counterparts

If you're a true crime fan, there's a brand new series for you to sink your teeth into - and this one promises to be gripping. Titled The Staircase, HBO's latest series follows the real-life story of novelist Michael Peterson, who was accused of murdering his wife Kathleen Peterson in 2001. Kathleen was found dead at the bottom of her stairs, hence the show's title, with the case also drawing attention as the subject of a Netflix docuseries back in 2018.

The first three episodes of The Staircase launched today (5th May) on NOW and Sky, with more dropping weekly going forward. So, if you're angling to know more about the real people behind the story, take a look at The Staircase's cast versus their real-life counterparts below.

All-round legend Colin Firth plays Michael Peterson, the man accused of murdering his wife, Kathleen. Michael's story was previously told in a Netflix documentary also titled The Staircase, with Colin bringing the true crime story to life in a whole new way.

The real Michael Peterson first went on trial in 2003, where he was initially convicted of murdering his second wife Kathleen - though he only pleaded guilty to killing her by involuntary manslaughter. It also emerged that Peterson's friend, Elizabeth Ratliff, had been found dead in similar circumstances to Kathleen (at the foot of her staircase) 16 years earlier - though Peterson wasn't charged with her death.

Toni Collette plays Kathleen Peterson, whose death is the focus of The Staircase. Toni + Colin Firth + Sophie Turner = a powerhouse cast that we're already obsessed with.

The real Kathleen Peterson was found dead at the bottom of her staircase (hence the show's title) on 9th December 2001. Kathleen's husband Michael was initially convicted of her murder in 2003, though a range of theories as to the cause of her death have made Kathleen's case particularly intriguing for more than two decades.

Sophie Turner is *finally* back on our screens, this time in the role of Margaret Ratliff, alongside Odessa Young who plays her sister Martha.

Sisters Margaret and Martha Ratliff were family friends of Michael and Kathleen Peterson - raised by the couple after the death of their mother, Elizabeth Ratliff. It later emerged that Elizabeth had been found dead in similar circumstances to Kathleen (at the bottom of her staircase), raising questions as to whether Michael was in fact responsible.

Patrick Schwarzenegger plays Michael Peterson's son, Todd Peterson, who stood by his father throughout the trial.

The real Todd Peterson (pictured in the middle) is Michael Peterson's youngest son with his first wife, Patricia. Now, Todd's Instagram lists him as a President and Founder of America Industries, and he's a prolific poster on the platform.

Olivia DeJonge plays Caitlin Atwater, Kathleen Peterson's daughter from a previous relationship. Caitlin initially stood by stepfather Michael during his trial, before later changing her stance.

The real Caitlin Atwater initially supported her stepfather Michael throughout legal proceedings. However, she later changed her mind after seeing pictures from her mother's autopsy. Years after the trial, Caitlin went on to reach a $25 million (£20 million) wrongful death settlement with Michael.

Parker Posey plays lawyer Freda Black in The Staircase, and her resemblance to the real life woman is pretty much uncanny.

Freda Black was one of the prosecution lawyers in Michael Peterson's murder trail, with the lawyer sadly later passing away in 2018.