Hartley High's final year is already chaotic enough.

Amerie, Darren, Quinni, Malakai, Cash, Sasha, Spider, Harper, Missy, Ant, and the rest of the Hartley crew are preparing for graduation while dealing with friendships, rivalries, relationships, secrets, and the uncertainty of what comes after school.

Then everything changes.

The entire group suddenly finds themselves inside a mysterious reaction room.

There are comfortable couches, snacks, a huge screen, and absolutely no way out.

A message appears:

WELCOME TO THE REACTION ROOM.

They soon discover that the screen can show practically anything:

• Their past

• Their future

• Alternate universes

• What-if scenarios

• Their childhoods

• Possible futures

• Memories

• Original characters

• Different timelines

• School moments

• Parallel versions of themselves

• Funny edits

• Emotional moments

• Things they never knew about one another

And everyone has to watch.

No skipping.

No leaving.

No hiding.

Which is particularly unfortunate for a group of teenagers who already have enough secrets between them.

Joining the Hartley crew are two new faces from rival school St Bruno's:

Noah, Amerie's boyfriend, and Sebastian "Seb" Johnson, Noah's friend.

Now Hartley High's graduating class has to sit together and watch their lives unfold on one giant screen.

And somehow, they're expected to behave.