Parallel universe (What If... Martha lost her Osterhagen key?)
From Tardis Wiki, the free Doctor Who reference
In a parallel universe, Martha Jones lost her Osterhagen key, being sure that she'd had it when she left UNIT HQ. (PROSE: "What If... Martha lost her Osterhagen key?" [+]Part of Time Warped!, Loading...{"namedpart":"What If... Martha lost her Osterhagen key?","1":"Time Warped! (DWA 90 feature)"})
