Bacteriophages are re-emerging as powerful allies in the fight against antibiotic-resistant bacterial infections and have long been key drivers of innovation in biotechnology. However, our understanding of phage biology remains dominated by a few classical models, leaving the potential of their vast diversity and of the abundant genetic dark matter in their genomes largely untapped. We are therefore studying newly isolated phages with remarkable capabilities, such as the elimination of dormant, antibiotic-tolerant bacteria, and have composed the BASEL collection, a curated set of diverse new model phages now widely used by the community. Our current work applies novel genetic technologies to uncover the molecular mechanisms behind the unique infection strategies of these phages and to reveal new principles of phage-host interactions. These insights will guide the selection and engineering of phages for new applications in biotechnology and for clinical phage therapy.