**Study Summary** This study is for adults with a type of liver cancer called hepatocellular carcinoma (HCC) that cannot be removed by surgery. It looks at a special pair of drugs, RYZ811 and RYZ801, which are used together to find and treat cancer. RYZ811 helps doctors see the cancer using a scan, and RYZ801 is the treatment itself. To join, you must be at least 18 years old, have confirmed HCC, and have tried other treatments that didn’t work. You cannot join if you have certain health problems or if you have had a liver transplant. **Key Points:** - **Duration & Visits:** Participants will go through different phases, but specific timeframes or number of visits aren't detailed here. - **Eligibility:** Must be 18+ with specific cancer conditions; certain health issues can disqualify you. - **Risks and Benefits:** Possible side effects and benefits will be explained during the study; always ask questions to understand them fully. For women of childbearing age and sexually active men, specific birth control measures are required. If you're interested, ensure you meet all criteria and discuss with your doctor.