The Bob Brothers All-Star International Circus was a circus that was ran by Bob and Robert Brothers.
Verne Brown and his new friend Chris, along with Marty McFly came from 1992 to watch the circus, only to find it in poor shape. An example of such included the employee who was the human cannonball being injured, with Marty being chosen to fire out of the cannon.
They soon found out that the circus was in the debt of farmer Mac Tannen as it was his land being used for the circus.
After accidentally causing damage to Mac's farm, Verne and Chris were put to work at the circus to pay off their debts, but then decided to hand out free tickets, as well as doing acrobatics when the trapeze artists quitting.
The performance proved to be a success, allowing Bob & Robert to payoff Mac Tannen.
The circus was eventually out of business by 1992, with Verne and Chris only being aware of it due to an older poster from a comic book shop.