Dragon Ball Super 73 begins with Jaco eating ramen at some restaurant and hearing weird music. On his ship he is carrying a small creature, who is named Watagash. This creature is in a small glass container, but it starts to break it, and runs away. Back on Earth, Gohan is typing some information on his computer, but immediately rushes to where Videl is to watch a commercial. This commercial is about Great Saiyaman vs Mr. Satan. Barry Kahn is playing the role of Great Saiyaman, and this probably shocked Gohan quite a bit. Barry is quite popular. Barry did not like the title of Great Saiyaman vs Mr. Satan, therefore, he asked a movie producer to change it to Barry Kahn in Great Saiyaman vs Mr. Satan. Mr. Satan shows Gohan, Videl, and Pan around the buildings where the movies are being filmed. In the meanwhile, Goku is training in King Kai’s planet, and he seems to be catching a cold. Mr. Satan wants to reveal to a friend that Gohan is the real Great Saiyaman, but Videl stops him from revealing the secret and says that not everyone wants to be famous like her dad. Barry starts to compliment Videl and offers to give her his autograph. Gohan is all like “you could have gotten an autograph.” Videl didn’t care for an autograph because she thinks Gohan is much cooler.
While the scenes for the movie are being prepared, Barry says that he doesn’t want to participate in the upcoming scene because he thinks an awesome actor like him shouldn’t get injured. He does have another actor to play his role, but using wires. However, the other actor seems scared and doesn’t want to get hurt. Gohan then tells a movie director that he would like to participate in the movie scene. Gohan is told that he’s an amateur. Barry is okay with Gohan participating in the movie scene, and says that he could become popular with the ladies. Gohan wants to participate in the movie so that when Pan grows up, she can enjoy the movie.
Gohan puts on the Great Saiyanman outfit. Barry is having thoughts to himself, and he is thinking about how he felt embarrassed because Videl ignored his flirtatious comments. Barry hopes that Gohan gets injured in the next scenes. An army tank is out of control and about to crash in a building, but Gohan immediately jumps on top of it, opens the ceiling of it, and rescues the person inside the tank. The movie directors really enjoyed Gohan’s performance and asked him to be their stuntman from now on. Gohan says that he was just excited due to wearing the Great Saiyaman costume. Videl tells Gohan “with the mask on, no one will see your face.”
Gohan starts to walk in the streets and wonders if he can memorize the movie script. However, a crime is going on in the streets and there are police officers. Krillin is trying to get the robbers to surrender. The robbers shoot Krillin with their weapons, but Krillin manages to dodge all the shots. Great Saiyaman rushes to the rescue, but as he punches through the wall where the robbers are at, he manages to knock Krillin to the ground. The robbers were recently released from prison and it turns out that Gohan had previously dealt justice to them. Earlier in this episode, Jaco was carrying a specimen named Watagash. Watagash looks like a weird bug. Watagash all of a sudden bites one of the robbers. The robber who got bitten became aggressive, punched his friend, became super muscular, and his eyes started to glow read. The robber challenges Great Saiyaman to a fight! The robber starts to throw punches at Great Saiyaman, and manages to send him flying out the window. Great Saiyaman sends the robber flying back to the building with a kick. Gohan was going to wrap things up with a kamehameha, but instead uses the Great Saiyaman Beam when he sees that the cops are on top of the building. Watagash left the robber, who was the host.
Everyone at the movie industry was becoming aware that Gohan is the Great Saiyaman. However, Bulma arrived to conceal Gohan’s identity, and she starts to tell the everyone else that Gohan had grabbed a spare Great Saiyaman suit from her place to use it only for the acting scenes. Bulma and Gohan successfully managed to conceal the identity of Great Saiyaman. During this conversation, a girl overhears everything that Gohan and Bulma are telling each other. This girl asks Gohan to help her with her movie lines. She wants Gohan to help her instead of Barry. Gohan asks her if they will practice at her house. The girl is all like “I thought you could fly me home.” She’s already aware that Gohan is the Great Saiyaman. She knows that Gohan is the one who defeated the bank robbers. She tells Gohan that she overheard his conversation with Dr. Bulma, and that she’ll keep the secret to herself. However, in return, she asks to fly behind his back. As Gohan is preparing to take her home, the girl sees a UFO. Jaco is right outside his spaceship. Jaco pulls out a Macrocosm Cannon from his ship. After this, Jaco says “I’ll vaporize you at the cellular level before things get out of hand, Watagash!” This episode ends with Jaco shooting his cannon to where Great Saiyaman and the girl are at.