We present a method for the simultaneous modelling and numerical simulation of PDEs on curved, two-dimensional manifolds which are defined implicitly by level sets of a scalar function over a bulk domain. The numerical method was called Bulk Trace FEM in [1] where it was applied to geometrically non-linear ropes and membranes. Herein, this method is extended to linear structures with bending action and shear deformation, i.e., Reissner-Mindlin shells. For the implicitly defined shells with middle surfaces implied by the level sets, a coordinate-free formulation of the mechanical model is required which follows [2], however, herein applied to infinitely many shells at once instead of only one single shell. Related approaches, mainly for transport problems, are shown in the overview article [3] and references therein. The bulk domain is discretized with higher-order, Lagrange-type elements and the boundaries of the structures are conforming with the boundaries of the bulk domain. Hence, a strong enforcement of essential boundary conditions is possible. However, the mesh is not aligned to the individual level sets (i.e., the shell structures) within the bulk domain and, therefore, this method is a hybrid between conforming classical finite element methods and fictitious domain methods, such as the Trace FEM [4]. This novel approach for the simultaneous analysis of shells is verified using classical bench mark test cases for one shell. Furthermore, higher-order convergence studies in the residual errors for the force and moment equilibrium, respectively, confirm optimal convergence rates. REFERENCES [1] T.P. Fries and M.W. Kaiser, On the simultaneous solution of structural membranes on all level sets within a bulk domain, Comp. Methods Appl. Mech. Engrg., Vol. 415, pp. 116223, 2023. [2] D. Schöllhammer and T.P. Fries, Reissner-Mindlin shell theory based on tangential differential calculus, Comp. Methods Appl. Mech. Engrg., Vol. 352, pp. 172-188, 2019. [3] G. Dziuk and C.M. Elliott, Finite element methods for surface PDEs, Acta Numer., Vol. 22, pp. 289-396, 2013. [4] D. Schöllhammer and T.P. Fries, A higher-order trace finite element method for shells, Internat. J. Numer. Methods Engrg., Vol. 122, pp. 1217-1238, 2021.