The mechanic has been suffering with guilt since he helped his secret lover Robert cover up Katie’s death.
He’s been punishing himself with excessive exercise, and it’s not only Katie’s murder that’s eating him up.
His relationship with married Robert will start up again and they even get some time alone when Robert’s family go away.
But Aaron’s happiness doesn’t last long, as the return of Robert’s wife Chrissie is hanging over them.
This causes Aaron to punish himself even more, leading to a horrifying accident.
After running himself into exhaustion, Aaron falls and damages his ankle. He eventually manages to free his ankle, but his tired state causes him to stumble down an embankment and black out.
Nobody knows where Aaron is or what’s happened to him, leaving him in a very dangerous position.
These scenes will air on 6 April and 7 April at 7pm on ITV.