The bad boy, played by Dan Ewing, is enjoying an affair with April Scott (Rhiannon Fish) when one of his ex-girlfriends arrives in the area, TV Week reports.
Full details of the character have yet to be revealed, but it is thought that April fears she will lose Heath once she learns of the new arrival.
Home and Away's new series producer Lucy Addario recently teased: "There's a juicy love triangle [coming up] between April, Heath and a gorgeous woman from Heath's past."
With the Bay's residents also suspecting that April's sister Bianca (Lisa Gormley) isn't over Heath, it sounds like the River Boy will be at the centre of gossip for some time to come!
Home and Away airs these scenes next week on Network Seven in Australia and late February on Channel 5 in the UK.
> Home and Away pair's shock one-night stand
> Home and Away lines up more April, Heath twists
> Home and Away Rhiannon Fish: 'April, Dex perfect for each other'
> Home and Away star Lisa Gormley chats to Digital Spy
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