Michelle's son Mark Fowler Jr made a surprise appearance in EastEnders tonight – and, of course, he's brought a big secret along with him from Florida...

Mark Fowler Jr has landed flip flop first into Walford as part of a sensational storyline that is EastEnders’ longest kept secret.

Played by Ned Porteous, Mark Jr, the son of Michelle Fowler, is a warm, caring and honest young man who has grown up in the sunnier climes of Florida. But he is also half Mitchell, a fact that his dad Grant Mitchell doesn’t know!

Will Grant finally discover the truth about his son?

Ned said: “Being part of two iconic families and the longest kept secret in EastEnders history is beyond exciting! I’m honoured to be here and can’t wait for viewers to properly meet Mark Jr.”

Mark Jr’s mum Michelle left Walford pregnant and fled to Florida, with only her brother Mark knowing the truth about the baby’s father. Since then Martin and Pauline found out the truth about his paternity, but he has never been seen on the Square… until now.

Mark Jr is coming to London in search of answers. But should he be careful what he wishes for? And will that dangerous Mitchell side come to the surface?

Watch > Ned being interviewed by ‘Uncle Martin’, AKA James Bye, here.

Ned is a relative newcomer to acting, having graduated from the Guildford School of Acting in 2015. Before EastEnders, he’s had small roles roles in Holby City, Suspects and Delicious.

No word on exactly how long Ned will be in EastEnders. Will it be a short visit or is he putting down roots?