On my weekly time card, I'm required to log ten hours a day for a regular eight hour shift as a PA in a television production company. So, for a regular 40hr week I'm paid 10hrs overtime that I never worked.

I believe they do this so they can list a lower hourly wage than they said I'd be paid.

They told me $550 a week for a 40hr week ($13.75/hr). Then they required me to list 10hrs a day.

What can I do?

IF you are a Non-Exempt employee AND you are actually working time that you are not being paid for THEN you need to file a wage claim with CA-DLSE. Labor law is very clear that Non-Exempt employees are paid based on actual hours worked.

However your question implies that you are not working unpaid hours. Past that, your situation makes no sense. CA minimum wage is $8/hr. By having you falsify your time sheet, your employer is risking you filing a wage claim for time you did not work. It is to the employer's advantage to under report hours worked, not over report hours worked.

I suspect that they are padding time records because they are getting reimbursed from someone else and that by lying about expenses so they are getting over reimbursed.