Johnny's parents were killed when he was only ten years old. He was raised by two separate family friends that he referred to as "uncles." Uncle Jess was portrayed by Edgar Buchanan. Uncle Joe was portrayed by Frank Ferguson.
In the early 1960s when TV-western mania reached its peak, an American magazine sponsored a contest for the actors who portrayed western heroes and villains. Since the climactic moment of so many shows was the classic quick-draw shoot-out, the actors had to acquire that skill to play their scenes. The magazine held a competition among some of the stars of the shows, firing blanks, aiming not at each other but downrange, and using an electronic timer. Quite a number of cowboy stars showed up to slap leather. Peter Brown beat them all and won the title of the fastest gun in Hollywood.
In Season 1, Dan was injured a total of 6 times and shot twice. Johnny was injured 4 times and never shot. Dan shot and injured 7 people, and shot and killed 24. Johnny shot and injured 3 people and shot and killed 12. Dan's more interesting injuries include being mauled by a bear and hit by a tree being used as a wagon jack. The most people shot and killed by Dan and Johnny in one episode in Season 1 were 5, in Lawman: The Gang (1959).
John Russell was only 37 - and looked even younger than that - when he was cast in this series. He believed that in order for a man like Dan Troop to have gained the kind of experience and maturity he possessed he would have had to have been in at least his mid-40s, so Russell had the makeup department streak gray through his hair and he lowered his voice when he spoke in order to appear several years older.
Speaking of recycled scripts, John Russell gets to act out the same story on two different shows. The script featured a retired gunfighter that let's the hero know that he can't use his shooting hand anymore. He goes to the widow of his former business partner and offers her money that rightfully belongs to her. The widow's son refuses and challenges the gunfighter to a shootout. The gunfighter refuses to back down, while the hero tries to talk him out of it. On Cheyenne (1955), Russell played the retired gunfighter. On Lawman (1958), he played the hero trying to talk the gunfighter out of the shootout.
In Season 2, Dan was injured a total of 3 times and shot 4 times (including one graze). Johnny was injured 6 times and shot 3 times (including one graze). Dan shot and injured 2 people, and shot and killed 22. Johnny shot and injured 1 person and shot and killed 10. Dan's more unusual injuries include stepping in a wolf trap and being bitten by a child. The most people shot and killed by Dan and Johnny in one episode in Season 2 were 4, in Lawman: To Capture the West (1960).
In Season 3, Dan was injured a total of 5 times and shot 4 times (including being grazed twice). Johnny was injured 5 times but was not shot. Dan shot and injured 2 people, and shot and killed 22. Johnny shot and injured 3 people and shot and killed 5. Dan's more unusual injury was being shot in his gun hand and having to then shoot left handed. The most people shot and killed by Dan and Johnny in one episode in Season 3 were 4, in Lawman: The Escape of Joe Killmer (1960) Even though other trivia indicates in season three, Warner Brothers began toning down the violence on the show, the Season 3 numbers did not really reflect this. Dan killed 22 people in Season 2 and 22 in Season 3. Johnny's kills were cut in half, though, from 10 to 5. Those shot and injured by Dan were 2 each season, while Johnny's shot and wounded numbers went from 1 to 3.
In Season 4, Dan was injured a total of 2 times and shot 3 times (including being grazed once). Johnny was injured 7 times but was not shot. Dan shot and injured 11 people, and shot and killed 19. Johnny shot and injured 5 people and shot and killed 9. Dan's more unusual injury was falling into a hole. The most people shot and killed by Dan and Johnny in one episode in Season 4 were 5, in Lawman: The Cold One (1961), in which Lily also killed one person. Lily was shot herself in Lawman: The Juror (1961).
At the start of season two, Peggie Castle was cast as Lily Merrill, a saloon owner. Over the course of the final three seasons, her relationship with Dan held many similarities with Matt Dillon and Miss Kitty of Gunsmoke (1955) fame.
Johnny quit his job as deputy three times during the series run. The first time was when he thought his biological father might have been an outlaw. The second time was when he thought Dan was trying to take credit for a kill that he made. The third time was after he shot a childhood friend, and didn't think he had the stomach for being a lawman anymore.
With the passing of Peter Brown at age 80 in March 2016, none of the actors portraying the three main characters are still alive. John Russell passed away in January 1991 at age 70 and Peggie Castle in August 1973 at age 45.