Martin Mystery
They Came From The Gateway (Part 1 of 2) (2x7)
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When M.O.M. ceases to return from her Jamaican vacation, Billy calls in Martin, Diana & Java to investigate (despite the fact that Martin has been temporarily suspended from the Center). They uncover what M.O.M. was really up to – she was on a secret mission to unlock the Gateway To The Underworld! Halloween theme music)