Some images from the past never fade.

Mr. Rythm, a horse that mesmerized audiences in the 1970s and ’80s with his ability to dance, is one of those memories.

The 16-3 hand American Saddlebred was a familiar performer at events across the country with owner and rider Darrel E. Wallen, longtime trainer and operator of Blue Moon Stables in Sedalia, Mo.

Mr. Rythm, an imposing chestnut at 1,200 lean pounds, had a large repertoire of dance steps, including a fabulous hoola number complete with grass skirt.

He was most famous for his ability to walk on his hind legs in an upright position, all the more impressive due to his size.

He made the Guinness Book of World Records with a walk of 357 feet, more than the length of a football field.

Wallen’s wife, Donna Marie, and son, Dan, are carrying on the family tradition now, continuing the training business at Blue Moon Stables in Decatur, Indiana, where Darrel Wallen eventually settled after retiring from traveling with Mr. Rythm.

Dan Wallen took time in 2006 to share some history about the famous duo.

Darrel Wallen was the son of Harry Wallen, who had a training stable in Independence, Kansas, from about 1900 to 1934. The business filled many necessary roles at that time, from draft horse work, to rental horses, to training for customers who had enough oil money that they continued to keep their horses going, even during the Depression. That training included “high school” maneuvers, not unusual at a time when most people had horse skills and the standard of training was high, Dan said.

His grandfather was the first to teach a horse to sit on his haunches, kind of a Wallen trademark, Dan said.

Harry Wallen eventually took a job in Sioux City, Iowa, training 40 white horses for the Abybekr Shrine Barn. His five sons, including Darrel, were trainers, as well.

Darrel Wallen eventually had his own Saddlebred show barn, Blue Moon Stables, at the fairgrounds in Sedalia from the early 1960s to 1972. He leased Barns A and B, training as many as 60 horses for clients from more than half the states.

Mr. Rythm, whose name is spelled without a second h, was born Aug. 4, 1968, at property nearby that was leased by Wallen. The colt was the son of Southern Rocket out of Lady Belva, both horses owned by Wallen.

His arrival during a thunderstorm led him to be named Born Free for a while. He was gelded at 2.

Once Wallen started working with the horse, the trainer was amazed how quickly his new protege learned.

They would go on to develop an act with more than 50 dance steps and tricks.

The pair’s first performance was in 1970, at a Boystown Horse Show in the St. Louis area, Dan believes. He said that after the two did their routine, they went back to their trailer only to be approached by several people who booked them for eight more shows before the day was over.

The act was such a success that Wallen chose to give up his training stable in Sedalia and travel full time.

Both single at the time, Wallen and the horse were the ultimate bachelors on an endless roadtrip.

Traveling in a trailer made by Campbell Coach, their home included full living quarters up front, complete with a full bath, a 4-foot tack room and a 12-foot square stall for the horse — all air conditioned.

Mr. Rythm was very particular about having a clean house, according to Donna Marie. If the horse used his bedding, he would then paw for Darrel Wallen to come clean it up.

He also was house-trained for trips to more elegant surroundings.

The horse would eat in the morning. Then before going to perform, Wallen would turn the horse around in the trailer, and Mr. Rythm knew it was time.

“He was a smart horse,” Donna Marie said.

Mr. Rythm kept up a schedule for years of traveling 100,000 miles annually and giving 100 performances. He was a guest in state capitols, governors’ mansions and grand hotels, and went up and down on elevators in the buildings as gracefully as he danced. He was ridden by 30 governors, featured on the game show “To Tell the Truth,” led the Kentucky Derby’s Pegasus Parade, and performed at Radio City Music Hall as well as under the St. Louis Arch, according to The American Saddlebred.

He was a guest of the St. Louis National Charity Horse Show at Queeny Park in the early 1980s, also appearing on the cover of the program.

Wallen had 40 different coats for himself and a several different bridles and plumes for the horse, so each ride had a different look. Mr. Rythm’s feet were painted to match the color of the day, Dan said.

Mr. Rythm also was noted for the checkerboard pattern on his rump, put on with a water sponge, 4-inch comb and hair spray, with a sequin added in each corner for spark, Dan said.

Perhaps the pair’s favorite performances were entertaining patients at Shriners hospitals.

“Wherever they went, he did shows for the children,” Dan said. “He loved children.”

Darrel Wallen met Donna Marie on the road; she had grown up on pleasure horses, then performed with Dan Anderson’s White Horse Troupe and the Lipizzaner show based in Florida. The two teamed up for horse shows, rodeos, circuses and mall shows before giving up traveling in 1985. They eventually settled in Indiana for family reasons.

But Mr. Rythm continued to perform into his 20s, as late as 1991. He was put to sleep in 1994 at age 26 after getting too old to get up and down.

Dan and Donna Marie Wallen continue to train, teach and perform.

Dan does a lot of training in the same high school tradition of his father. He also trains horses and students in traditional English, Western and driving. He can get horses ready for Wild West shows. He has two ponies that he taught to get up on barrels with all four feet and roll them. And, as if all that’s not interesting enough, he trains exotic animals, such as zebras, buffaloes, camels, donkeys and llamas.

When asked what types of personalities zebras have, he said they’re very skittish and wild and will try to run from everything.

“It takes a lot of trust” to train them, he said.

The family has not come upon another horse like Mr. Rythm.

Dan said his father had some others prospects, including one called Mr. Rythm Jr. for a while.

Darrel Wallen also had a promising black Saddlebred born in 1998 who was coming along nicely as a 4-year-old until a freak accident took his life.

“That was really hard on my dad,” Dan said.

Darrel Wallen passed away himself, on Sept. 21, 2005.

Dan said his father was still breaking colts in 2003 — very fit and able to do the work even then. His life was cut short by complications from surgery.

Both members of the famous dancing team may be gone, but no one will ever forget their showmanship and stamina as one of the greatest exhibition acts ever.