Things got personal for Stone when footage emerged of the girl several years earlier stating she was sexually abused by her father Martin (Chris Walker).
Taking Fletcher, Armstrong, and PC Benjamin Gayle to the home of the suspected rapist, they lay in wait until a group of thugs burst in and savagely assaulted him, responding to the callout and arresting the men responsible.
After forcing her way onto an undercover operation, Stone laid down the law as she put herself in danger, attempting to kiss him before pulling out as he was drawn in, stating that her suspicions about him fancying her were confirmed.
The events of Shockwave take place the day after the undercover operation, Armstrong notices Keane tease Stone as he told her to be careful whilst out on patrol.
During the rescue efforts, Keane found a man masquerading as a doctor who sexually assaulted a woman trapped in a car during the blast.
Superintendent John Heaton introduces DI Karen Lacy (Liz May Brice) of SO15 to DCI Meadows and the rest of CID, who has been tasked with investigating what was a total of 8 deaths between the first two bombings and the third that killed Keane.
In the series, the man arrested was paranoid and twitchy, refusing to comment, and a new clue emerged with a letter pointing them in direction of a delivery made to their suspect's neighbor.
When DC Grace Dasari linked a repeated clue, "The Elvis Four", she realized it was an anagram of the four evils, a belief of the four worst things made more prevalent by the internet (pornography, racism, identity theft, and pedophilia).
With the criminal's ideals identified, DC Dasari invited bomb targets Jeff Bowman and Carl Adams to the station to be questioned about their links, along with Michael Gilcrest's friend James Marfield.
A memory stick found at the scene was used to tell the investigating team they had four hours to find a bomb before a sex offender would be blown up.
Stone, back at work after his attack on Smithy, joined his posse as they investigated a software company that was linked to Bowman and Marfield.
As he was arrested, Webb identified Colin Moore as James Marfield, making DCI Meadows realize the prime suspect was under their noses all along.
Stone ducked out of Keane's funeral to find Mrs. Waverley, and as he and Webb found her car, they worked to rescue her baby from the back seat.
As Meadows and Dasari found Colin, they tried to talk him down, but he set the bomb off anyway, however, Stone was able to rescue the baby before Mrs. Waverley's car exploded.