  We perform molecular dynamics simulations of a supported molecular thin film.
By varying thickness and temperature, we observe anisotropic mobility as well
as strong gradients of both the vibrational motion and the structural
relaxation through film layers with monomer size thickness. We show that the
gradients of the fast and the slow dynamics across the layers (except the
adherent layer to the substrate) comply, without any adjustment, with the same
scaling between the structural relaxation time and the Debye Waller factor
originally observed in the bulk [Larini et al., Nat. Phys., 2008, 4, 42]. The
scaling is not observed if the average dynamics of the film is inspected. Our
results suggest that the solidification process of each layer may be tracked by
knowing solely the vibrational properties of the layer and the bulk.
