How do you unlock griphook on Harry Potter years 5-7?

To unlock Griphook in "Harry Potter: Years 5-7," you need to progress through the story until you reach the mission titled "Gringotts." During this mission, you will encounter Griphook, and after completing specific tasks and challenges, he will become a playable character. Make sure to collect enough studs and complete the objectives to ensure his unlock. Once achieved, you can use Griphook in free play mode.