Speaking in an interview with Holy Soap, Bower appeared to suggest that the milestone instalment will contain a twist involving Paul Robinson, marking his long history with the programme.
The show boss revealed: "[The episode] includes an iconic character, who has in fact been in the show since episode one. He's our favourite person, the one we love to hate, and it's really been a nice slow burn, and we set up different scenarios of other characters who interact with him, and it's pretty special.
"It's pretty special because the whole block also includes a wedding, so I can tell you that."
Asked whether any surprise comebacks are in store, Bower replied: "I like if we are going to have returning characters that they're part of the story, [that] they don't just walk in and say 'g'day' and walk out again. And so we've had, for example, Rosemary Daniels from New York.
"We will have Simone Buchanan, who played Dan Fitzgerald's wife, and we did try others, but for various reasons we were unable to get them through their commitments. It's not for lack of trying."
Neighbours reached its 25th anniversary in March and its 6,000th episode is expected to be the highlight of the soap's year-long celebration.