It's summer break for Mark and his friends, but supervillains don't take a vacation. Mark is forced to face the consequences of Omni-Man's double life.

The Grayson household is upended when Mark returns to Earth with surprising new responsibilities. The Guardians of the Globe face dangers both at home and away.

As Mark attempts to salvage his personal life, a new villain arrives, presenting Invincible with his greatest challenge yet. Donald grapples with his past.

Mark takes a stand, unaware of the ramifications for his family, the GDA, and even the Guardians. Cecil remembers his past and Eve makes an important decision.

Mark struggles to teach Oliver what it means to be a superhero. Debbie explores a new relationship and a changed family dynamic.

A powerful new figure challenges Mark's idea of what's right and what's wrong. Rae approaches Rex with a big life decision.

Earth's greatest heroes join forces to fight an unimaginable threat.

With the world still reeling, a dangerous stranger arrives - testing Mark to his limits and beyond.