A person diagnosed with HIV today might never experience AIDS, nor transmit HIV. Advances in treatment effectiveness and coverage has made the UN 2030 vision for the 'end of AIDS' thinkable. Yet drug adherence and resistance are continuing challenges, contributing to avoidable deaths in high burden African countries, especially among men. The mood of global policy rhetoric is hopeful, though cautious. The mood of people living with HIV struggling to adhere to life-saving medication is harder to capture, but vital to understand. This paper draws on ethnographic fieldwork with a high burden population in Kenya to explore specific socio-economic contexts that lead to a potent mixture of fatalism and ambition among men now in their thirties who came of age during the devastating 1990s AIDS crisis. It seeks to understand why some HIV-positive members of this bio-generation find it hard to take their life-saving medication consistently, gambling with their lives and the lives of others in pursuit of a life that counts. It argues that mood - here understood as a shared generational consciousness and collective affect created by experiencing specific historical moments - should be taken seriously as legitimate evidence in HIV programming decisions.