At high noon tomorrow, Eastern time, Amazon’s Jeff Bezos, Facebook’s Mark Zuckerberg, Apple’s Tim Cook and Google’s Sundar Pichai will appear via videoconference before Congress in a long-awaited showdown with the House of Representatives antitrust subcommittee. If you are planning to watch, make sure you have a comfortable chair and plenty of snacks. The grilling could last as long as six hours.

Don’t be disheartened if things get off to a slow start as both committee members and the tech executives make opening statements. Although the CEOs prepare long written statements that are released ahead of time, their live remarks are likely to be limited to five minutes each. But it is during the Q&A where things should get interesting. If past experience is any guide, most of the action will occur in the first 90 minutes. After that, you may see the back-and-forth become a bit repetitive as various lawmakers take turns posing the same provocative questions to the same witnesses.