Filamentous materials are found throughout biological and synthetic systems, where they play important roles in providing structural support, transporting materials, and enabling dynamic reorganization. Even at the single-filament level, the dynamics can be remarkably rich because of the interplay between connectivity, flexibility, and the flows generated by the filament or the surrounding active fluid. Biological filaments such as actin and microtubule are inherently complex due to the biological process therefore; we use colloidal filaments whose flexibility and activity can be independently controlled. For active filaments where monomers generate flow, we show how elasticity, hydrodynamic interactions, and active flows lead to behaviors such as bending, rotation, and self-propulsion. On the other hand, we study the dynamics of passive filaments in an active bath generated by bacterial suspensions and show that the characteristic length scale of the bacterial ‘jet’ governs the filament dynamics. These controllable model systems provide a framework for understanding how activity, elasticity, and hydrodynamic flows shape filament dynamics.