Jonny first appears in February 2007 when he strikes up a friendly working relationship with bisexual Grayson Sinclair. Grayson's wife, Perdy, is worried that they are having an affair and invites him to a dinner party with her gay friend, Paul Lambert. They get on and soon start dating. After six months together, Jonny moves into Victoria Cottage with Paul, Paul's father, Rodney Blackstock, and Emily Kirk. He confides in Paul that, as a teenager, he suffered from an eating disorder as a result of loneliness and unhappiness. During his time in Emmerdale, Jonny sets up an aerobics dance class and fitness club.
When Rosemary King's meddling leads to Perdy being sectioned, Paul spends more time with Grayson. He acts as go-between as Perdy refuses to see Grayson and Paul develops feelings for Grayson and Jonny asks Paul to marry him. Paul accepts but has a one-night stand with Grayson. When Grayson tells Paul it meant nothing, Paul feels guilty and tells Jonny but convinces Jonny that it was a one-off and on 3rd March 2008, they get married at Hotten Registry Office. Later that day, they have a ceremony at Home Farm as neither can tell their parents they have already married.
In July, Katie Sugden gives birth to Grayson and Perdy's son. Katie and Grayson had agreed to raise him together and allow Perdy access but Katie changes her mind when she learns about Grayson and Paul's one night stand. Katie keeps her new plan to herself and after delivering the baby in the back of Matthew King's car, Perdy phones Grayson with the news but is convinced by Katie and Matthew to leave with the baby. Jonny, however, initially refuses to believe that Paul did not warn Grayson but is coming round until he sees Paul and Grayson hug. Although, Paul said nothing had happened and he had not reciprocated, Jonny told Paul that he could no longer trust him and left on 31st July 2008. He later texts asking for a divorce.
In January 2009, Jonny requests they close their joint bank account. Paul's friends, Lily Butterfield and Leyla Harding, see how upset he is and decide to try and reconcile him and Jonny. This causes Jonny's mother, Patricia, to visit. After some confusion, Paul convinces Patricia that he still loves Jonny, who is now in Australia. He plans to visit Jonny there to try and rebuild their relationship but Val lies and tells him that Rodney has a heart condition, hoping to stop him leaving while Lily gets in touch with Jonny and arranges a meeting between him and Paul. While they both love each other, Paul tells Jonny he cannot leave Emmerdale because of his father's condition. However, on the day Jonny is due to fly out, Paul finds out his mother was lying and leaves for Australia.