Methuselah Children is the first novel and introduces Lazarus Long. From there there is no real chronology, though Time Enough for Love is almost exclusively about him.
Lazarus Long, the oldest human alive in the universe, tells his life story to the sentient computer in charge of the planet Secondus. This is done in a series of interconnected short stories, with sections of quotations "From the Notebooks of Lazarus Long" between. Lazarus is thousands of years old, and is ready to die, but his descendants decide to find something to reawaken his interest in life.
The series you are thinking of is Hustle.
Robert Cummings was in a TV series called "My Hero". If this is the show your are looking for, Julie Bishop and John Litel were two people who were in the series for 17 episodes along with Robert Cummings.
Robert April never appeared in the Original Series, he appear in one episode of the Animated Series "The Counter-Clock Incident" and was voiced by James Doohan
Robert Langdon is in a series of novels, the best known being The DaVinci Code.
In no particular order: Honda's B series. Honda's K series. Ford's BD series. Toyota's 4age series.
a series of activities meant to produce a particular result
There is no public information about Lauren Tarshis planning to write more books specifically about Emma-Jean Lazarus at this time. However, she may continue to write new stories or series in the future that focus on different characters or themes. It's always a good idea to keep an eye out for updates from the author.
The Henderson Boys
Robert Varkonyi
1979
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