HMAS is about Samuel a Petty Officer in the Australian Navy, who loves his job but has a hard time returning to his girlfriend Jenny. Jenny is a house maiden constantly looking after her mother, Ellen, who is bedridden with diabetes. Ellen was married to a Navy man, and doesn't want her daughter ending up with a broken heart like she did. Jenny and Ellen constantly fight over the presence of Samuel, which leads to the untimely death of Jenny. How will these two survive?