Enforced: Bob's actor has to rest his eyes after being injured in an accident and they're behind schedule for that season. They're forced to write the injury into the plot so they can finish filming on time.
Lampshaded: "You do realize you're blind, right, Bob?" "Yes, I realize, but I'm going to defeat Alice anyway. Where there's a will, there's a way."
Alice attempts to make Bob less of a threat to her Evil Plan by blinding him with a flash bomb, deafening him with a loud explosion, or otherwise putting him "out of commission" as a hero.
Alice the Evil waits for Bob to be injured by happenstance before putting her Evil Plan into effect rather than doing it herself.
Exploited: Charlie the prankster trips Bob while he's blind.
Defied: Bob knows that fighting Alice while blind would be risky, and waits for his vision to return.
Discussed: "I could defeat Alice with my eyes closed." "In that case, you wouldn't mind if I blinded you."
Conversed: "That's Bob, all right! He goes blind, and it doesn't stop him from his goal."
Implied: In the background of a scene, Bob is seen with dark glasses and a white cane. He does not appear anywhere else in the episode.
Deconstructed: Bob's blindness makes his goal much more difficult.
Reconstructed: Luckily for him, Bob has a friend who helps him out in his time of need.
Played For Laughs: Because he's blind, Bob walks straight past Alice's Schmuck Bait traps.