How long can Kieren keep his dark secret from his half-sister Roo?

With Keiran’s history of drinking and domestic abuse, Alf and Martha have been anxious about his “fresh start” in Summer Bay– and this week, his good-guy act begins to fall apart in a telling act of rage.

At the Stewart household, Martha (Belinda Giblin) and Alf (Ray Meagher) discuss how to handle Kieran’s (Rick Donald) presence in town.

In recent episodes, Martha revealed Kieran is her son and has a sorry history of violence and substance abuse.

Their relationship soured to the point where she called the police and fled.

But now, after being in rehab, he’s asked for a second chance. Martha is surprisingly accommodating of his request, but Alf isn’t.

“Kieran has some mental health issues, and he’s still really struggling with addiction, and past family stuff, Rick, 35, tells TV WEEK.

“It’s a lot of baggage for him to bring into the Bay.

“That’s what drew me to the role.”

Alf’s daughter Roo (Georgie Parker), however, doesn’t know about his violent past.

She offers to show him around town, causing Martha to be worried.

Before they leave, Alf takes a moment to have a firm word with Kieran and they both agree on the boundaries: one wrong move and

he’s gone.

Half-siblings Roo and Kieran find they have more in common than they expected as they share their grievances and past – Kieran only touching on his alcohol addiction.

Roo admires his strength to mend fences and encourages him to stick around for a while longer.

“Kieran is really trying to make amends for his past, and having a half-sister in Roo is a really nice way to make a fresh start,” Rick says.

While it seems he may have won over some people in the Bay, he makes a terrible impression on others.

After his tour, Kieran goes looking for work so he can earn an income to cover the cost of renting his caravan.

Kieran seizes the chance to make an impression, but catches Jasmine at the wrong time.

She tells him to hand his résumé into reception and she’ll follow it up – but Kieran won’t back down and refuses to leave until she offers him

an interview, or better yet, the job!

Jasmine’s old friend Lewis (Luke Arnold) has to intervene and Kieran storms off. Outside the surf club, he explodes in an aggressive outburst.

“He just pushes too hard, because he’s so desperate to make amends and to be this new guy,” Rick says.

“But because he’s so desperate, he’s aggressive. It becomes too much and he punches a tree – he’s not in a good headspace.”

With such a short fuse and a violent streak, his next outburst is bound to see someone get hurt.

Who’ll be unlucky enough to cross his path?