With so many events at so many weird hours (anyone fancy watching some water polo at 2am?) it can be hard to keep up with the Brits you want to support.
But don't worry - we've got you covered.
Here are the Brits you'll want to watch out for on Day 4...
David has claimed an Olympic silver at each of the last two Games in Beijing and London and he will be hoping to claim the elusive gold in the men's canoe slalom C1 an event in which he has won top honours in the 2013 and 2015 world championships. The top 10 from the semi-final at 5.30pm BST on Tuesday afternoon reach the final, which is slated to get under way at around 7pm.
Siobhan will be hoping to add to Britain's early successes in the pool. If she made it through her heats and semi-finals of the 200 metres individual medley, the Commonwealth Games gold medallist will race in the final at roughly 3.15am on Wednesday morning. Away from the Britons, Michael Phelps and Chad le Clos go head-to-head in the 200m butterfly final about an hour earlier.
The women's gymnastics team.
Earlier in the day, the British women's gymnastics team will be hoping to medal in the final, which gets under way at 8pm.
Tonia Couch and Lois Toulson.
This pair will compete in the women's synchronised 10m platform final at approximately 8pm while Britain's equestrian riders are in action from 6pm.