Slow Horses season 4 kicks off with major character death – but there’s a twist

The episode opened with Roddy witnessing a terrorist bomb attack on Westacres shopping centre, after River and Louisa were seen getting a drink. She convinced him to go and visit his grandfather David, after he told her he was suffering from dementia.

Separately, a confused David became anxious that someone was following him, and holed himself up with a gun. While we didn't see him, we then heard River come in the house and head up to the bathroom.

Becoming nervous that this 'River' wasn't who he claimed to be, David went upstairs and shot him dead! He then panicked, as he realised he had accidentally killed his grandson.

As the episode wound on, David went missing and MI5 attempted to track him down, while Jackson Lamb identified the body, confirming it was indeed River that was killed.

As the Slough House team learned the news, they mourned him - particularly Louisa, who blamed herself for telling River to visit his grandfather, and seemingly leading him to his death.

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Except, this wasn't quite what happened – as many viewers would have already guessed, River wasn't actually dead, and David had instead killed an imposter. River had then taken the opportunity to go into hiding and investigate.

Jackson had worked out River's plan as soon as he had seen the body, and had played along in order to keep River safe, and his movements a secret.

Exactly how River's plan came together, or how it will play out remains to be seen, but it seems likely we'll find out more when the second episode arrives next week.

Of course, fans could be forgiven for thinking River had actually bitten the dust – the show certainly hasn't been afraid to kill its darlings in the past, with Olivia Cooke's Sid Baker missing since season 1 after she got shot, and Dustin Demri-Burns's Min Harper getting killed in season 2.

Slow Horses season 4 will stream on Apple TV+ from Wednesday 4th September – sign up to Apple TV+ now.

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