The actress's troubled character Whitney Dean is about to become embroiled in a case of sexual exploitation when she falls for the charms of a handsome stranger named Rob who ends up using her for his own financial gain.
Whitney first meets Rob - played by former Shameless star Jody Latham - in next week's episodes and is relieved when he offers her a place to stay following her recent problems.
However, Whitney is making a terrible mistake in getting involved with Rob as his true intentions will only make her troubles far worse.
Speaking to Inside Soap, McGarty explained: "I did a lot of research before filming this storyline. I met teenage girls who had been exploited sexually and they told me about their experiences. It was shocking to learn about their manipulation and abuse by people they had thought they could trust."
EastEnders bosses have worked closely with Comic Relief while devising Whitney's storyline. The plot will culminate in a special ten-minute episode due to air as part of the charity's televised telethon on Friday, March 18.
McGarty added: "Comic Relief has funded work around this issue for the last 10 years. When EastEnders tackles a difficult topic, specialist help is always sought to present an accurate picture - so I hope we're raising awareness for young people."
> First Look: Jody Latham as EastEnders' Rob
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