Keith Rice has taken over the part of Finn and has already begun filming with the Channel 4 soap.
Finn - brother of Sinead and stepson of Diane - was previously played by Connor Wilkinson for a year from September 2010. The character later departed the village to live with his father Rob.
The teenager's return scenes will air in mid-April, making the O'Connor clan a bigger presence in the village again.
Alex Fletcher, who plays Diane, first hinted at Finn's return in an interview with Digital Spy last month.
She said at the time: "I think it's nice to have that single mum and daughter situation. That's the reality of life and there's a lot of single parents out there. Although I do like that, it's not to say that the rest of the family won't make a comeback. It may not be just the two of us forever."
Finn's biggest storyline was an underage sex plot in 2010, which saw him father a baby daughter with Amber Sharpe.
New recruit Rice has previously appeared in three-part children's series Rocket's Island, which was made by Hollyoaks' production company Lime Pictures. His other screen credits include parts in Little Crackers, Small Creatures and Casualty 1907.
Hollyoaks airs weeknights at 6.30pm on Channel 4, with first look screenings at 7pm on E4.
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