A laser-induced photochromic dye tracer technique has been applied to investigate the hydrodynamic structure of free falling liquid films inside a vertical tube (ID = 50.8 mm) over the film Reynolds number (Re-L = 4 Gamma/mu) range of 1408-6549. :Flow visualization data indicated significant differences between the measured velocity profiles and Nusselt's predictions in wavy turbulent films. Also, the experimental data have shown that wave-induced turbulence produces a flat velocity profile within the large disturbance waves and also affects the flow in the substrate film depending on the wave amplitude. Present data clearly indicate that the large disturbance waves do not carry large fractions of the liquid mass as previously believed.