|Charlie Clausen, as Zac MacGuire|
|Residence||6 James Street|
|Family|| Ethan McGuire
|First Appearance||22 january 2013|
|Portrayed by||Charlie Clausen|
Zac is a prison education officer who encounters Casey Braxtonwhen he breaks up a brawl. Clausen revealed that Zac has been asked to keep an eye on Casey by Natalie Davison. The actor stated that Zac is "a good guy", who began working in the prison system after spending time inside when he was younger. Clausen said "At a young age he made a mistake, and that has dictated every choice he's made since." During the Holly storyline, Jaci Stephen from the Daily Mail commented "Monday is a miserable day for Holly, when she tries to kiss Zac and is rebuffed. Try to? I'd resort to chloroform for that kind of hot totty."
Natalie asks Zac to look out for Casey when he is taken to Crestview Correctional Centre. He introduces himself to Casey, but Courtney Freeman teases him. Zac provokes Casey into punching him to earn him the respect of other inmates. Zac begins to jog with Natalie and reveals that he still has feelings for her. When her ex-boyfriend Darryl Braxton (Steve Peacocke) appears to ignore her, Natalie kisses Zac and they begin dating again. Darryl witnesses the kiss and he confronts Zac about Casey being attacked in prison. When Courtney stabs Casey, Zac tries to help him get released from prison early. He also arranges for Jamie Sharpe to be transferred, which costs him his job. Zac then successfully applies for a teaching position at Summer Bay High. On his first day of teaching, Zac takes his class off school property and is reprimanded by principal Bianca Scott. Zac is liked by the students and helps Jett James cope with the loss of his mother, Gina. Student Holly Chapman develops a crush on Zac. Holly flirts repeatedly with Zac but he shrugs off these advances. Holly claims that Zac sexually harassed her and talks to the papers, potentially ruining Zac's career. When Bianca calls the department and gives her opinion on the matter she is demoted as principal. Zac helps the students protest and Bianca is reinstated. Natalie tells Zac that she is leaving Summer-Bay to find her mother, leaving him upset.
When Hannah Wilson arrives in the bay asking for Zacs help to help his nephew and niece because they are becoming part of a cult. Zac agrees and begins to look after the twins with Hannah. The two start a relationship which soon comes to an end as the twins tell them that they are starting to ignore them.
Zac delivers the twins to a music festival and tells them to call him when they want to come home. They never do and Zac finds out that they have been kidnapped by Zacs brother Ethan. With the help of the Braxtons, Hannah and Zac rescue Oscar and Evelyn.