Welcome back to Spoiler Alert, where we break down the endings of some of the best games on the market.  This week we head back to paradise lost with Deep Silver's Dead Island Riptide, the follow-up to its popular first-person zombie action/adventure game.

The last time we left Dead Island, we found the survivors looking at a hopeful future while flying off the island to safety.  Things are not as they appear and they land right back in the thick of the zombie outbreak that had affected Banoi.  So immediately they'll need weapons to try and figure out what happened.

Careful, there are spoilers ahead that give away a great deal of the game.  You're better off finishing it on your own first before you read what happens.  Now let's see how the story continues...

The beginning takes a few hours after the events that occurred in Dead Island.  The four remaining survivors – Australian bodyguard Purna, Hong Kong police officer Xian Mei, rapper Sam B. and ex-American football player Logan Carter – land on an aircraft carrier following their flight off the island.  They are then taken into custody by the ADF Colonel Sam Hardy and civilian VIP Frank Serpo.  They're put into the ship's brig until answers can be sorted out.

The survivors meet John Morgan in the brig, who explains that Serpo stopped the military's evacuation of the island to begin with.  During this time, you can track down excerpts from Morgan's diary that said how he canceled the evacuation in favor of firebombing the entire area of Banoi that was infected.

After passing out from the sedatives provided by Hardy and Serpo, the player wakes up to find that the ship has mysteriously become overrun with zombies.  Serpo managed to flee before this began, though he crashed his helicopter into a rock shortly thereafter.  The player then fights through the remains of the ship, working with a few surviving soldiers locals before eventually overcoming the captain, but you're unable to stop the ship from crashing.

The player then reawakens again to find themselves on the shore of Palanai, another tropical island.  You'll do a little investigating before finding yourself in a survival facility, running across a World Health Organization (WHO) researcher by the name of Harlow.  It turns out the zombie infection has spread onto that island as well.  Your character of choice will eventually run into Colonel Hardy once more, who explains what happened.  It turns out that Serpo's organization is interested in taking the Kuru strain that's causing all the infection and weaponizing it, and the same nuclear strike that was planned for Banoi is being considered for that island as well in order to cover up the evidence and stop the infection.

The team then travels to Henderson per Hardy's advice, fighting zombies along the way to a nearby army base.  From ther you're forced to crawl through an underwater tunnel since there are no bridges intact.  A researcher by the name of Dr. Kessler explains along the way that the virus mutation was a reaction from exposure to chemical weapons.  They have to be careful, since these weapons were actually stored in the tunnels and could very well act as a mutagen to turn the virus that makes these four characters immune into something beyond their control.

Following their clearance from the tunnels, Harlow tests an infected victim to see what the results are, accidentally creating a monster that the players must stop.  The players then do battle with a number of escaped prisoners who have taken control of the pier, unleashing an inexplicable fury in the process.  Kessler explains this may be due to the fumes from the chemical weapons, which are acting out their mutagen purposes and warns that they should avoid further exposure.  The team eventually does reach Henderson and Harlow leaves after taking shelter in a movie theater.

Your team manages to get a hold of Serpo, who survived the crash.  He explains that there is no nuclear strike planned and that Hardy shouldn't be trusted.  The Colonel admits he made up the nuclear strike to push the team forward, but counters that Serpo can't be trusted either.  He feels that Serpo only wants to evacuate the immune survivors to continue his research.  Serpo arrives and Hardy tries to prove his point, only to be shot and killed.  The survivors shoot down the helicopter in response.

Serpo survives and is found near the crash site, where he explains that Harlow is immune and secretly looking to seize data and a vaccine from a quarantine zone in order to continue evil deeds.  Your team heads to the zone shortly thereafter and finds Harlow.  She explains that the outbreaks were actually started deliberately, in order to test the power of the virus; a vaccine doesn't exist after all.  The lab's staff then inject her with mutagen and she goes on a rampage as a giant beast.  The team has no choice but to inject themselves and fight back, eventually killing her.

Your team then makes it to a boat, only to be greeted by Serpo again.  He admits that he did orchestrate the outbreaks, but offers medical help for your team if they come with him.  Instead of trusting him, you eventually leave him to the zombies and evacuate the island with the remaining zombies in your party.

Cut to six days later, when the team's boat washes up on yet another island abandoned.  The game concludes with growling heard and the doorknob being turned open from the inside, no clue as to what happened to the survivors inside.  Guess we'll find out in Dead Island II, won't we?

Dead Island Riptide is available now for Xbox 360 and PlayStation 3.