Semi-mad scientist Jake Burroughs, his beautiful daughter Deety, her strong love interest Zeb Carter, Hilda Corners (“Aunt Hilda” if you prefer) and their time/dimension-traveling ship Gay Deceiver yak and smooch their way though many time periods in many universes (including that of Lazurus Long), soon realizing the true nature of the world as pantheistic multiperson solipsism.

In Heinlein’s first version of this novel, written in 1977, the middle third of the story takes place on Barsoom, but in the 1980 published version, Barsoom was replaced by a futuristic British Mars

Sure, others have pulled that 20th century actress forward to make modern films with spectacular failure, each attempt spawning a branch universe unconnected to the 21st century of time traveler Det Gruber, but none of the others took into account the psychological factors in the way that Det’s employers have done.