We　report　on　the　finding　of　hidden　hyperchaos　in　a　5D　extension　to　a　known　3D　self-exciting　homopolar　disc　dynamo.　The　hidden　hyperchaos　is　identified　through　three　positive　Lyapunov　exponents　under　the　condition　that　the　proposed　model　has　just　two　stable　equilibrium　states　in　certain　regions　of　parameter　space.　The　new　5D　hyperchaotic　self-exciting　homopolar　disc　dynamo　has　multiple　attractors　including　point　attractors,　limit　cycles,　quasi-periodic　dynamics,　hidden　chaos　or　hyperchaos,　as　well　as　coexisting　attractors.　We　use　numerical　integrations　to　create　the　phase　plane　trajectories,　produce　bifurcation　diagram,　and　compute　Lyapunov　exponents　to　verify　the　hidden　attractors.　Because　no　unstable　equilibria　exist　in　two　parameter　regions,　the　system　has　a　multistability　and　six　kinds　of　complex　dynamic　behaviors.　To　the　best　of　our　knowledge,　this　feature　has　not　been　previously　reported　in　any　other　high-dimensional　system.　Moreover,　the　5D　hyperchaotic　system　has　been　simulated　using　a　specially　designed　electronic　circuit　and　viewed　on　an　oscilloscope,　thereby　confirming　the　results　of　the　numerical　integrations.　Both　Matlab　and　the　oscilloscope　outputs　produce　similar　phase　portraits.　Such　implementations　in　real　time　represent　a　new　type　of　hidden　attractor　with　important　consequences　for　engineering　applications.　Published　by　AIP　Publishing.