Fuller was known for his deep “charcoal” voice, his roles on the popular Western series Laramie as Jess Harper and Wagon Train as Cooper Smith, and as Dr. Kelly Brackett in the medical/action drama Emergency!

He was also in several movies, including: The Brain from Planet Arous (1957), Teenage Thunder (1957), Return of the Seven (1966), Incident at Phantom Hill (1966), What Ever Happened to Aunt Alice?

At the urging of friends, Simpson, Jr., joined the Screen Actors Guild, changed his name to Robert Fuller, and embarked on a career in acting.

In 1953, he again had uncredited parts in Gentlemen Prefer Blondes (which starred Marilyn Monroe) and the Doris Day classic, Calamity Jane.

Boone suggested that Fuller study under the tutelage of Sanford Meisner at New York City's Neighborhood Playhouse.

[5]Fuller became an immensely popular character actor, guest-starring in dozens of television programs including Buckskin, The Big Valley, The Californians, The Restless Gun, The Lawless Years, U.S.

He also made appearances in ABC's The Life and Legend of Wyatt Earp and Mickey Spillane's syndicated Mike Hammer.

On February 24, 1959, Fuller guest-starred as Joe Cole in the "Blind is the Killer" episode of NBC's Cimarron City, a young gunfighter seeking a reputation who found his target in mayor Matt Rockford played by George Montgomery.

(This appearance propelled him into a lead role seven months later in Laramie with Cimarron City regular John Smith.)

In the summer of 1959, Fuller guest starred as young outlaw Buck Harmon in the episode "The Friend" on the ABC/Warner Bros. series, Lawman.

When the outlaw gang comes to Laramie, Buck switches sides to help his old friend, Deputy Johnny McKay (Peter Brown).

Smith had already been cast as Jess Harper; Fuller was asked to screen test for the character of Slim Sherman.

When it ended its run in 1963, Fuller jumped to another Western, Wagon Train alongside John McIntire (a veteran film actor, a two-time guest-star on Laramie), Frank McGrath, and Terry Wilson.

[8] Horton had already departed from the cast a year prior to Fuller’s stepping in to complete the series’ final two seasons.

He portrayed the ill-fated military Captain William Judd Fetterman in "Massacre at Fort Phil Kearney" on NBC's Bob Hope Presents the Chrysler Theatre.

He had already cast singer and actress, Julie London, a best friend of Fuller's, in the role of Dixie McCall, Chief Nurse of The Emergency Room.

The persistent Webb convinced him to accept the role of Dr. Kelly Brackett, Chief of Emergency Medicine, at the fictitious Rampart General Hospital.

Webb then reminded Fuller, much less politely, that Western shows had been repeatedly cancelled over the previous five years and that the genre was on the decline.

had been reduced, because not only did the show go into a completely different direction, he also wanted to look for more work in Westerns and go fishing with his friends; the series then focused much more on Randolph Mantooth and Kevin Tighe’s characters.

He did several "bandstand" gigs with Bill Aken's Los Nomadas rock group at holiday festivities in Whiskey Flats, California.

While acting as grand marshal for the local Memorial Day parade, he performed the 1950s song "Caribbean", singing the same verse over and over.

[16] On October 9, 2010, Fuller, Drury, and Don Reynolds participated in the Wild West Toy Show, sponsored by Bob Terry in Azle, Texas near Fort Worth.

[20] On March 18, 2006, a bronze sculpture of Jess Harper on Traveller was awarded to him by the Robert Fuller Fandom and the National Festival of the West.