Jimmy sometimes is hired on with temporary jobs onboard freighters during college vacations but he often lands in jail because of some kind of misunderstanding with the police who doesn't believe that his father is the famous Charlie Chan. The incarceration generally serves to justify Jimmy's "just happen to be in the neighborhood" presence when his father arrives on a case in Charlie Chan in Reno (1939) and Charlie Chan in Panama (1940).

In his initial appearance, Jimmy already has an appetite for detective work. "I could be the best detective on the island with your help," he tells his father. Charlie however is a little less optimistic— "I'm afraid you overestimate abilities of parent." Jimmy is always eager to assist his honorable detective father, most of the time without permission, and Charlie often has his doubts about Jimmy's usefulness—"Father who depend on son is happy or foolish according to son." Despite his good intentions though, Jimmy often gullible, providing more than occasional comic relief—"Young squirt merely chip masquerading as block."

Victor Sen Yung, whose original name was Sen Yew Cheung, was born October 18, 1915 in San Francisco's Chinatown. When he was 12, he took a job as a houseboy for a family on Nob Hill to help finance his future education. He later graduated from the University of California with a degree in economics and did some graduate work at UCLA and USC.

As did Keye Luke, Yung got into acting by shear happenstance. He was employed as a salesman for a chemical company and came to the 20th Century-Fox studios one day with samples of a new flame retardant to sell. Instead of closing the sale, Yung was persuaded to take a screen test for the new role of Jimmy Chan. In his role as Jimmy Chan, Yung appeared in all his films with Sidney Toler. Because of his military service with the Air Force in World War II, Yung was replaced with Benson Fong as Tommy Chan, the Number Three son when Monogram took over the series in 1944.

In 1946, Yung returned to the series reprising his Jimmy Chan role in Shadows Over Chinatown. Two films later, Sidney Toler died in 1947 and Roland Winters was picked to carry on the role of Charlie Chan for Monogram's final six films. Along with a new actor to play his honorable father, Yung was without explanation, now cast as Tommy Chan for five of the six final Monogram films and also mysteriously upgraded as Charlie's Number Two son.

Besides changes in his character from Jimmy to Tommy and his seniority among his brothers, Yung himself also underwent several name changes and spellings. In all ten films at 20th Century-Fox, Yung was credited simply as Sen Yung. When he returned to the series following military service, he was billed as Victor Sen Young but was credited as Victor Sen Yung in his final film of the series, The Feathered Serpent (1948). As to why the different names and spellings throughout the series, no one knows for sure.

Besides his appearance in 18 Charlie Chan films, Yung had roles in more than 35 other films, many of which were stereotypical for Asian actors. In some he had key roles, such as Ong Chi Seng in Billy Wyler's The Letter (1940) with Betty Davis, which Yung felt was his best performance, and as Frankie Wing in Flower Drum Song (1961). In addition to films, he found work in recurring roles in several television shows. He was Chuen in Kung Fu (1972), cousin Charlie Fong in Bachelor Father (1957-62), and was perhaps best recognized as Hop Sing, the Cartwright's irascible cook and houseboy, in Bonanza (1959-73). It is ironic that Yung was cast as a cook because he actually was a talented Cantonese-style cook. In 1974 he penned the Great Wok Cookbook (as Victor Sen Yung), which was dedicated to his father, Sen Gam Yung.

Unlike some of the other actors from the Chan and Bonanza series, financial fortune did not follow Yung. Virtually penniless and alone, he died tragically November 9, 1980 in a North Hollywood tenement from accidental carbon monoxide poisoning due to a gas leak in the stove.

Fong is cast with Sidney Toler as his honorable father in six Monogram entries but is dropped from the series after completing Dark Alibi (1946). Toler died on February 12, 1947 after a long illness from intestinal cancer and Roland Winters was tapped to continue the Chan role in The Chinese Ring (1947). As was the case when Oland died, there was also a shuffle among Charlie's children. Yung continued in the series, but he did so now as Tommy Chan, who was cast as the "Number Two son." The change in character name and number for Yung is probably due more to carelessness in the continuity of writing the screenplays than for any other reason. Of the three actors to portray Tommy Chan, Benson Fong's characterization, intentionally or not, comes off as the one who was the real bumbler.

Lee, Jimmy, and Tommy occasionally converse in fluent Chinese in many of the films, sometimes to their humble father when excited; more often though to pretty Chinese girls, like those portrayed by Barbara Jean Wong, Shia Jung, Iris Wong, and Jean Wong, that were included in the plots to add a dash of anticipated romance. However, Tommy's flawless conversational Spanish while in Mexico City during a scene in The Red Dragon (1945) is a big surprise when compared to Lee's French in the earlier Charlie Chan in Monte Carlo.

Besides the Charlie Chan series, Fong appeared in nearly 45 other films. His two favorite roles were that of a servant in Keys of the Kingdom (1944) with Gregory Peck and Vincent Price, and the family patriarch Wang Chi-Yang in Flower Drum Song (1961). Like Keye Luke and Victor Sen Yung, Fong also found additional work in television series such as Perry Mason, Family Affair, Kung Fu, Mission: Impossible, and It Takes a Thief.

Fong opened Ah Fong's, a restaurant on Vine Street in Hollywood in 1946 at the suggestion of his friend Gregory Peck. In time there were to be four more—in Encino, Beverly Hills, Anaheim, and one on Sunset Boulevard, but only one remained when Fong retired in 1985. As a bit of trivia, the next to last episode of the TV show Bewitched in 1972, revealed that Darin Stephens (then played by Dick Sargent) who worked for an advertising agency, had Ah Fong's Restaurant as one of his clients.

Benson Fong died August 1, 1987 at age 70 from complications of a stroke and was survived by his wife, five children and three grandchildren.

Like many of his siblings, Eddie can't resist the self-appointed urge to assist his father in solving the murder. There is one scene when Eddie and Birmingham Brown arrive to meet Charlie at the house where a murder had been committed earlier that evening. With unabashed conceit, Eddie asks of his father, "Now that I am here Pop, what type of murder have we got and how soon do you wish me to produce the murderer?" Charlie retorts, "Every time you open your mouth, you put in more feet than centipede."

Unfortunately, nothing is known about Edwin Luke and whether he had other film appearances besides The Jade Mask. Older brother Keye Luke, who was interviewed and quoted by Ken Hanke in his book, Charlie Chan at the Movies: History, Filmography, and Criticism, was noticeably silent on any details about his younger brother. Even Keye Luke's New York Times obituary, written by Peter Flint, made no mention of Edwin.

In "Olympics," a female murder suspect is presumed to be wearing clothing made from the fur of a white fox. Every time Charlie Jr. sees a woman wearing white fox fur, he quickly points out the woman, however a different one each time, to his father—"Look, white fox fur!" Eventually the senior Chan loses his patience and orders his son to walk home as punishment.

When Jimmy Chan is introduced three films later in "Honolulu," the Number Two son label is now Jimmy's for the remainder of the 20th Century-Fox films. As if there were already not enough confusion about the numbering of Chan's sons, Layne Tom portrays his second of three different sons in "Honolulu," but is now "Number Five son" Tommy Chan, who eventually rises up to the Number Three and then Number Two son at Monogram with different actors. Go figure!

Willie's only film role is rather inauspicious when at the film's beginning, he and Jimmy sneak into their father's office at the police station at night to see if Willie's teacher had sent Charlie a copy of his report card in the mail. Their father suddenly enters his office and uncovers Willie's deception for his being there, as Charlie had already received the unflattering report card in that day's earlier mail. Charlie sternly points to Willie that, "In Honolulu schools, E not symbol for excellent." Although he can forgive his son's bad report card, Charlie is unforgiving with his son's attempt at tampering with the U.S. mail. "What chance has a kid got when his father is a detective?" Willie says dejectedly.

As punishment, the younger Chan is to assume the "proper position" across his father's knee for a spanking. Just when Charlie is about to deliver the first strike, he is unexpectedly interrupted by an old friend from Scotland Yard, who realizes that he has just stumbled upon an old fashioned spanking. Chan explains the situation as, "Sometimes quickest way to brain of young sprout is by impression on other end." Having escaped punishment, Willie breathes a sigh of relief while rubbing his bottom and confesses to Jimmy that he's grateful that Scotland Yard arrived just in time.

Layne Tom's first film appearance was that of sitting on Clark Gable's shoulders in San Francisco (1936). He also had a role as the native boy Mako in The Hurricane (1937) featuring an all-star cast that included Dorothy Lamour, Jon Hall, Mary Astor, Raymond Massey, and John Carradine. However, he would be best known for his roles as three different sons to the same father in the Charlie Chan films.

Tom is married to Marilynn Chow, whose aunt, Jean Wong, herself had appeared in two Charlie Chan films: The Red Dragon (1945) and The Chinese Ring (1947). They have two daughters, Laurie and Joanne, the latter now known professionally as Kiana Tom, a well-known fitness and aerobics personality on ESPN, who is just getting into films herself. When once asked about her father, Kiana mentioned that Charlie Chan at the Olympics (1937) and The Hurricane (1937) are his favorites. More than 60 years later after "Olympics" was made, both Kiana and her mother still tease Layne about the mysterious "lady in the white fox fur."