Soap Insight: David's blackmail plot in Corrie

Coronation Street's unhinged teen David Platt - played by 22-year-old Jack P. Shepherd - steps up the pressure on his mother Gail's (Helen Worth) boyfriend Joe McIntyre (Reece Dinsdale) this week, as he capitalises on the knowledge of his painkiller addiction.

Having coaxed the truth about Joe's pill problem from Graeme (Craig Gazey) - who also supplied his latest fix - David relies on the old adage 'knowledge is power' to blackmail him in the hope of reconciling with his ex-girlfriend - Joe's daughter Tina (Michelle Keegan).

However, with Tina about to buy a house with her new partner Jason (Ryan Thomas), Joe faces an impossible task.

"David now has it in his head that Tina listens to what Joe has to say - for instance it was Joe who initially put it into Tina's head that David was a bit of a bad lad and for her to be careful in her relationship," Shepherd explains. "So David realises that Tina is likely to listen to her dad. It's just another stab at trying to win her back as all his previous attempts have failed. He just can't accept that he has lost Tina to his brother-in-law Jason.

On Monday, David pocketed Joe's pills and burned the container on a bonfire, Joe believing that the pills were still inside. David, however, intends to resell the tablets to Joe at an inflated price. With Joe suffering withdrawal symptoms and his business ailing at the hands of the recession, he struggles to find the cash to pay David for his next fix.

Shepherd smiles: "Joe's completely unaware that they're the same pills he originally bought from Graeme. It's a real plan of genius. He actually tells Joe that the pills are from an old prison contact and he initially says that they'll cost £50 - but then ups the price to £100."

Desperate for money, Joe steals cash from Gail's purse and when she notices, she immediately believes David to be the thief. When confronted, though, the youngster turns the situation to his advantage. Shepherd goes on: "David's about to spill the beans but Joe steps in just in time and admits that he took the money, saying that he needed some building supplies."

Joe's attempts at talking Tina into giving David another chance only serve to set alarm bells ringing in her head. Shepherd continues: "Joe seems to make things worse. He has a word with Tina and tells her to take things slowly with Jason and suggests that he's still not over Becky. Tina thinks this is really weird and then Jason and Tina go round to the Platts' and challenge Joe's views."

David's seething, though, when he later overhears Jason and Tina declare their love for each other, before discovering that Joe's agreed to fit a kitchen for them free of charge. Shepherd says: "David's devastated - he just can't move on from Tina. I think as long as Tina is on the street then David will always pursue her. She's his first love."

As Joe's condition continues to spiral, he edges closer to breaking point and next week, his anxiety escalates to new heights - Joe threatening the locum doctor for a prescription, before breaking into the medical centre in an attempt to collect his own…

Shepherd adds: "Joe has a lot to lose because if Gail found out he was hooked on the drugs, it would probably spell the end of his relationship…"