The New Original Wonder Woman - S1-E1
Revealing mistake: When the elderly woman fires the submachine gun at Wonder Woman, the sparks created by her bracelets are bigger and brighter than usual, and we can see the wires under both of her arms to help create those special effects. We can even see the wires' shadows on the wall behind her.
Wonder Woman vs Gargantua - S1-E7
Revealing mistake: After Erica shows Gargantua the window of Steigler's location, when the gorilla climbs up the building we can see the end of the hairy sleeves, and the human wrists/hands of the stuntman in the gorilla suit (then, on his way down we can see the end of his hairy pants at his ankle, as noted in another mistake). (00:12:40)
Wonder Woman vs Gargantua - S1-E7
Revealing mistake: When Gargantua has Steigler under his arm and is carrying him down the pipe, you can see the cuffs at the bottom of the pants legs on Gargantua, even though he's supposed to be a real gorilla and not wearing any pants. (00:15:27)
Wonder Woman Meets Baroness Von Gunther - S1-E2
Revealing mistake: After Wonder Woman saves Tommy from the falling ladder, when she uses her golden lasso to descend with Tommy (just a doll) we see her lasso (actually a thin rope) and its shadowy reflection on the windows, but we can also see the glistening of the stunt woman's safety cable as well.
Formula 407 - S1-E12
Revealing mistake: After Major Keller leaves in the car with Steve and the formula, when Wonder Woman rushes in front of Maria to protect her when she's being shot at, the wired remote that controls her bracelet sparks is visible in her left hand, as she moves her arms to deflect the bullets.
Revealing mistake: When one of Wotan's fellow Nazis in the rubber boat starts shooting toward Steve, in the closeup of Wonder Woman deflecting the bullets, one of the wired remotes that control her bracelets' sparks can be seen in her right hand, and as she starts walking toward the camera we can also see the other remote in her left hand.
Wonder Woman vs Gargantua - S1-E7
Revealing mistake: While the circus crowd is gathered around the cage with Gargantua, there's a closeup of the gorilla as he roars and we can see the stuntman's human teeth behind the gorilla's teeth. It happens again in Gargantua's closeup while he's climbing up to Steigler's window.
The Feminum Mystique: Part 2 - S1-E6
Revealing mistake: When one of the Nazis brings Drusilla a hot meal while she's being held in the deserted warehouse, in the shot just as she whacks him in the stomach we can see the stunt cable over the Nazi (stunt double) which lifts and pulls him back.
Formula 407 - S1-E12
Revealing mistake: When Wonder Woman catches the first grenade and tosses it away, it falls 20 centimetres to the left of where the explosion takes place. If you watch carefully, you'll notice glittering sand where the explosion occurs, revealing where the powder was.
Formula 407 - S1-E12
Revealing mistake: During the fight in the lab, Trevor's stunt is noticeable.
Formula 407 - S1-E12
Revealing mistake: At the Ambassador's residence, when Wonder Woman jumps out of the balcony, the stunt trampoline's black canvas, bouncing upwards, is perfectly visible.
Formula 407 - S1-E12
Revealing mistake: On the beach, Wonder Woman's stunt is noticeable because of her shorter hair.
Revealing mistake: When the explosions go and the place starts to shake, neither the trees outside nor the objects in the lab move an inch, revealing the camera trick. Later on, the group walks towards a table and things do shake.
Wonder Woman vs Gargantua - S1-E7
Revealing mistake: When Gargantua grabs Steigler, he is replaced by an obvious doll with stiff hands and rubber legs that bend awkwardly. (00:15:01)
Wonder Woman vs Gargantua - S1-E7
Revealing mistake: When a man runs towards Gargantua and is launched upwards, one can see the trampoline the stuntman uses.
The Feminum Mystique: Part 2 - S1-E6
Revealing mistake: Wonder Woman arrives at the island gardens, and the floor she stands on has a protruding object. Then the bad guys throw a smoke bomb at her. The shot swaps back to Wonder Woman, and an explosion occurs right where the protruding object was. (00:21:35)
The Feminum Mystique: Part 2 - S1-E6
Revealing mistake: When Wonder Woman gathers with the rest of the girls, there are black spots used as actor marks on the floor. There's one where Wonder's mother walks to and stops at when she arrives.
Fausta, the Nazi Wonder Woman - S1-E3
Revealing mistake: When Wonder Woman fights against Mueller, he is replaced by an obviously younger and thinner stuntman.
Fausta, the Nazi Wonder Woman - S1-E3
Revealing mistake: When Wonder Woman launches a thug up in the air and inside a crate, one can see the glaring safety cable that holds him up.
The New Original Wonder Woman - S1-E1
Revealing mistake: When Wonder Woman is pushed against a wall, the wall shakes, revealing it's made of cardboard. (01:32:30)
Answer: Not just Grundy but everything that could link Diana and her Wonder Woman identity. A links to B, then to C.
Did Randy know that Diana was really Wonder Woman?