Facebook CEO Mark Zuckerberg is set to testify in front of the Senate Judiciary and Commerce Committees on Tuesday afternoon, and most people expect it will be a grilling.

The social-media giant will face tough questions on Facebook’s role in hosting content from Russian troll farms that attempted to interfere with the 2016 presidential election. He will also face scrutiny over the Cambridge Analytica scandal, in which a Trump-aligned data firm inappropriately used the personal data of at least 87 million Facebook users to conduct political ad-targeting work.

Zuckerberg will return to the Hill again on Wednesday to face another grilling from the House Energy and Commerce Committee.

Watch below: