Summary:

A large group of students are left waiting for rescue after the island their school is on gets hit by a tsunami. After a month with no sign of rescue, they are forced to plan their own way of surviving and escape. Weird things begin happening and all hell breaks loose between the survivors as they begin to lose hope of ever going home.
Each main characters backstory is shown, showing how they became the people they are now with no adults around. Most show a broad range of emotions and regret for things they've done wrong.

Personal opinion:

I was actually surprised by how much I ended up liking this show. Each episode ended with a cliffhanger, making it easy to binge watch.
Kraam is the most interesting, not only because he should have died in the tsunami, but also because he seemed connected to the island itself. I would have liked to see a bit more of the island's abilities though. The characters were believable as they began to lose hope and fall apart.
A good show to check out if you like stranded, survival typed shows.