The Tower season 3 ending explained: What happens to Steve and Kieran?

Previous seasons have tackled a myriad of hard-hitting topics, and the new instalment is no different, exploring the urgent topic of knife crime.

Returning cast member DS Sarah Collins (played by Gemma Whelan) is tasked with the grisly case, which soon gets under her skin as well as bringing her into conflict with DI Kieran Shaw (Emmett J Scanlan), who is heading up a major undercover operation set up to bring down South London drug kingpin Shakiel Oliver (Daniel Adegboyega).

Kieran is working with unlikely partner DC Steve Bradshaw (Jimmy Akingbola), and despite their previous run-ins, the pair seem intent on bringing down Shakiel for the greater good.

Caught in his crossfire, though, is young Ryan Kennedy (Lamar Waves), who was witness to the stabbing and becomes increasingly involved in Shakiel's dodgy dealings.

So, how does it all unfold? Read on for a full breakdown of the ending of The Tower season 3.

The Tower season 3 ending explained: What happened to Steve and Kieran?

The final episode starts with Ryan's mother calling Sarah after Jermaine King - who is also the person that stabbed and killed Spencer - kidnapped Ryan's sister Tia the night before.

Jermaine has escaped custody, and Sarah calls Kieran to tell him about it but he's frustrated. He explains that this eventually means that Shakiel will start providing machine guns to teenagers, and it may very well end in the death of Ryan or his sister.

About to secure a big weapons deal, Shakiel is on the move with Steve, and the pair do the deal with one of their clients, swapping cars in the process.

But when they're cornered by armed police, Shakiel attempts to make a run for it. Even though he's about to reach for his gun, he eventually concedes and is arrested after the police find a car full of weapons.

Watching on, though, is Ryan, who had plans of shooting Shakiel but thought against it at the last minute. However, in secretly hiding out by the scene, Ryan sees more than he bargained for and spies Steve shaking hands with officers - meaning he is the one working with them.

Shakiel is arrested for importing weapons, an arrest that Kieran has been waiting to make for some time. Although it's a ruse, Steve is also arrested, but in the back of the car, Kieran calls him to tell him that Ryan is missing amidst the kidnapping of his sister.

In a bid to try and see where Ryan is and knowing how he's been visiting Steve regularly at his flat, Kieran tells Steve to return there to see if Ryan will come over. At the same time, Lizzie spots Ryan hiding out on the CCTV and realises he must've caught on to Steve following Shakiel's arrest, so calls Kieran.

Just as Ryan turns his phone back on, he gets a call from Tia's phone and it's Jermaine, who calls him a snitch and says that he's going to hurt his sister unless he meets him. They arrange a meeting point at 14 Foley Street, and at the same time, Ryan spots Steve walking down the road.

Talking to Lizzie, Kieran says that they turned off the internal camera in Steve's flat, so when checking the external CCTV, Lizzie sees that Ryan has ambushed Steve on his way into his flat with a gun. If she was allowed to have rewound the footage in the first place, they could've spotted Ryan at Shakiel's arrest and possibly stopped all of this.

While Sarah is out surveilling the street where Ryan and Jermaine agreed to meet, she realises that Jermaine is driving away and is set to go and meet Ryan at Steve's address. Back at Steve's flat and across the road, Kieran and Lizzie try to monitor the situation from across the road, but when they hear a gunshot, Kieran says he has to go in.

Ryan is very angry to learn that it could be Steve who has been snitching on him - the very thing he himself has been accused of. He says that the next gunshot will be aimed at Steve, but Kieran comes to the door to try and ease the situation.

Back by Jermaine's car, Sarah sees that the car has been set alight and smashes open the boot to rescue Tia, who is tied up in there. She thankfully rescues her in the nick of time, and calls Kieran to let him know that Tia is safe. As Ryan points the gun at Kieran, he accepts the phone call and Tia tells Ryan that she's alright and that he should come home.

But when Ryan gives Kieran back his phone, Kieran tells him that he needs to think of himself in this, and that Jermaine can be arrested for Tia's kidnap.

But just then, both Ryan and Lizzie spot Jermaine walking to the flat. Not wanting to let Jermaine get to the flat, Lizzie leaves where she's hiding out but is spotted from the window by Ryan, who knows she's a police officer as she was the one who previously arrested him.

Ryan grows angrier as he realises that he's been lied to by Kieran and Steve and tries to lean out the window, seemingly in a bid to shoot Jermaine himself. A shot rings out and at the same time, Lizzie approaches a knife-wielding Jermaine, who is quickly intercepted by police.

Back in Steve's flat, it's initially unclear who is wounded, but as Steve walks out of the flat unhurt, Lizzie makes her way inside and sees Kieran struggling for his life on the floor as he has been shot by Ryan. He's bleeding out but is being attended to by the emergency services. Lizzie tells him she loves him as Ryan is being handcuffed.

Turning up at the Shaw household, DC Parker (Harriet Webb) informs Kieran's wife Mary that he's in critical condition, but she quickly closes the door and says she needs to get her bag.

Once in the garage, Mary smashes up the incriminating mobile phone (from season 1 and Farah's death) that she's been keeping a hold of and does so with a hammer. Parker stops her and later takes her to the hospital to see Kieran.

We learn that Kieran has died of his injuries, and at the hospital, Mary informs Lizzie that she's destroyed the phone.

What happens to Ryan in The Tower season 3 finale?

Steve hands over a USB of evidence to Sarah and tells her to get Shakiel for all of this, not just the importation of weapons. Back at the police station, Sarah plays one of the audio files to one of Shakiel's gang members, Jerrell.

Although he seems loyal to Shakiel, the audio file is of Shakiel referring to Jerrell as his "dog" and so, understandably, Jerrell starts to rethink remaining loyal to someone who views him in such a way.

The final moments of the episode see Steve enjoying his life again – or at least trying to as he's seen chilling with his sons. Lizzie too is clearly overcome with grief and Sarah is at home, watching the news story unfold about Kieran's murder.

We learn that Ryan has been arrested and charged with Kieran's murder and get a montage of flashbacks that show how quickly he was swept up unwittingly into Shakiel's world.

As he's driven away in the police van to go to prison, he takes out a small note - clearly from Steve - that reads: "You did it, my guy."

The Tower season 3 airs on ITV1 and ITVX from Monday 2nd September to Thursday 5th September at 9pm.

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