Act I is the first act of Dead Island, taking place just after the prologue. It is set in the Resort area of Banoi, and is the first time the player encounters the Thug and Suicider special infected types.
Act I starts after the survivors have saved John Sinamoi from the Walkers outside during the Prologue. Sinamoi gives them a quest to retrieve a keycard that unlocks the Lifeguard Tower and tells them about the voice from the radio and their apparent immunity to the virus. He also states that they'd have to use the Lifeguard Tower to contact the voice from the radio, since it might be their only ticket off of Banoi. After securing the Lifeguard Tower, the heroes are tasked with helping out two other survivors while Sinamoi comes up with a new plan. After retrieving fuel to burn the dead zombie bodies in the lifeguard tower and obtaining parts needed to fix the satellite receiver, the heroes are then asked to find some juice and canned food for the group. It is later revealed to be insufficient and Sinamoi decides it would be best to head into town to look for supplies. The way there is blocked by a barricade so the heroes are sent to retrieve the armoured truck from the hotel parking lot. They then bring it to Jin and her father to reinforce. After bringing the reinforced truck back to the lifeguard tower, Sinamoi informs them of a down helicopter near the beach and sends them to investigate it for supplies. The heroes rescue a survivor named Nikolai and escort him to safety at the nearby bunkers. They then return to the lifeguard tower to join up with Jin and head into Moresby to look for supplies.