|Allies||Jupiter, Pete, his parents|
|Affiliation||The Three Investigators|
|First Appearance||The Secret of Terror Castle.|
|Last Appearance||The Mystery of the Cranky Collector.|
Robert "Bob" Andrews was one of the three members of the titular detective firm, The Three Investigators, also including Jupiter Jones and Peter Crenshaw, and was designated, Records and Research. As he had broken his leg his leg "in umpteen places" while rolling down "some five hundred feet of slope", which was a record, he had to wear a brace. Although it was a nuisance to him, it didn't annoy him for most of the time. The brace, however, was removed sometime after they solved the mystery behind the whispering mummy, and a week before they started to investigate the green ghost.
At the start of the series, Bob wore a leg brace and was not always up to strenuous physical activity. He was assigned all the research work. His library work, which was part time, also helped in this. While he lacked the deductive skills of Jupiter, like Pete, he had high analytical ability. He was also very courageous; his courageousness, according to Jupiter, was comparable to that of a lion. His father, a freelance newspaper reporter, also helped in solving cases by giving valuable clues and information.