Megan is Declan Macey's "glamorous" half-sister, she arrives at Home Farm to stay with Declan after he contacts her about getting involved with a big project.
Throughout November and December 2013, Declan began physically abusing Megan by hitting her across the face on numerous occasions. Eventually, Katie witnesses one of Declan's attacks and sticks up for Megan, despite Megan saying that it was just a misunderstanding. On Boxing Day, Megan enters a fire at Home Farm, believing that Declan is trapped inside, but she is unaware that he caused the fire and left earlier with Charity Sharma. Megan becomes trapped herself but is later freed by the fire brigade. Megan isn't very pleased in April 2014, when Declan reveals he is engaged to Charity and that she is pregnant with his child. They plan to get married on 15th May 2014, although Charity's former boyfriend and cousin Cain Dingle and his fiancée Moira Barton also intend to marry on that day. Only Megan, Robbie and Charity's son Noah attend, as the rest of Charity's family are at Cain's wedding. Just as the registrar pronounces them husband and wife, Megan sounds the fire alarm, which infuriates Charity. When she finds out what Megan has done, Charity slaps her and a small fight ensues, although Declan stops them.
Unbeknownst to Declan and Megan, but Charity has her pregnancy terminated as she never wanted a child. When Charity is having an argument with Megan, and Megan accidentally knocks Charity to the floor, Charity uses the accident to fake her miscarriage. Megan, becoming ever more guilty, reveals this to Declan, who shouts at her and throws her out. Megan then begins a relationship with Declan's enemy, Jai Sharma, and becomes business partners with Leyla Harding.
When Megan's son Robbie finds out about this, he supports his mother and attempts to break into the abortion clinic to obtain Charity's medical records to expose her. However, Robbie is caught by the police and is given a cautioning. But Declan finds out and takes Charity to a remote cottage, where he destroys the car engine and Charity's phone so she can't escape. Charity figures out that he is trying to kill her and tries to escape. Robbie also figures this out to and takes Megan to the dock where Declan is trying to kill Charity. Robbie goes to the boat and tries to save Charity, who is about to be shot with a flare by Declan, but Declan fires the flare as Robbie climbs onto the boat, killing him instead. Declan looks for Robbie but can't find him so he goes back to the boat and tries to kill Charity, but Charity hits him with a small metal suitcase, and everyone thinks he's dead.
On the day of Robbie's funeral, Megan discovers Declan is still alive when he sneaks into Home Farm. Declan holds Megan hostage and reveals the truth to the Dingles about framing Rachel Breckle for the Home Farm fire. Declan shows Megan that the gun was fake, apologises to her and kisses her goodbye before going on the run.
In August 2015, Megan discovers she is pregnant with Jai Sharma's baby. A week later, Megan began bleeding and went to the hospital where she was told the baby is fine, but Megan fakes a miscarriage after seeing the lengths Jai went to try get custody of his son Archie. Megan left Jai and moved in with friend Sam Dingle, who agreed to keep her pregnancy a secret from Jai. Jai later found out Megan had lied about losing the baby when he sees her cradling the bump, and a few days later, accidentally runs her over. Megan and the baby are fine and Megan discovers she is expecting a daughter.
On 3rd March 2016, whilst driving to a scan with Sam, she asked him to pull over so they could talk. Sam got annoyed and wandered off into the woods, and Megan went after Sam. Megan went into labor in the middle of the woods, and they were both unable to call an ambulance as their phones were left in the car. Sam went to try find help but is accidentally shot in the bottom by Joanie Wright, who was taking a shooting lesson. Jai came across their car and later found Megan and took her to hospital where she gave birth to their daughter. The baby was rushed into the NICU and Megan and Jai are informed that the baby had been starved of oxygen at birth and it was possible that their daughter would have cerebral palsy. A few days after birth, Eliza suffered a seizure, and when Jai couldn't bear to watch his daughter like that, Megan got annoyed and disallows Jai to see Eliza.
In 2017, Megan went out with ex-conman Frank Clayton. He later had an affair with Charity and Megan was infuriated. She later "forgave" him, and agreed to his idea of building places in Spain to sell as timeshares. Frank proposes to Megan, and she accepted - but Frank was unaware of her plan to set him up for fraud. Megan had planned to sell timeshares to people, plant the money under Frank's bed, call the police, and leave the village with the money and start afresh with Eliza. Charity got wind of this plan and forced her way in. When Frank started selling timeshares to close friends and family, Megan decided she couldn't go through with it, but Charity stole Frank's phone and sent seductive texts to herself and showed these to Megan. Megan was further enraged, and decided to give their friends the money back at the end. On 24th August, Megan and Charity's plan was into action. But when Megan learnt of Frank's secret wedding in Spain, she told Charity she couldn't go through with it, so Charity locked Megan in the cellar of The Woolpack and called the police on Frank. Frank found the bag of money and the one way ticket as the police arrived, and he made a run for it, until they finally caught up with him at The Woolpack. Frank despised Megan and Charity for this, and Megan's attempts at a reconciliation were to no avail.
Megan gave Frank some time and manages to get back into his life. One day, Frank finds a stray dog he names Tip, and pleads with Megan to have him stay with them. Megan eventually relents, but discovers she has an allergy to dogs. Frank tries to convince Megan to let Tip stay, reminding her how much Eliza loves her, but Megan won't be swayed. However, she and Frank manage to get Jai to look after Tip, lying that he is house trained. Jai takes the little dog in temporarily, but ends up falling in love with her, to the annoyance of his father Rishi.
In 2018, Megan had a brief affair with Graham Foster. This led to a brief split from Frank, but they soon reconciled. Megan later broke up with Frank after finding out he had returned to his con-man ways, and later began a relationship with Graham.
"I've only been here five minutes and you ditch me already." (First line, to Declan Macey)