[BB11UK]

Very good ideas, but I don't want ANOTHER "evil Big Brother", it's so old now!

Here is my launch night:
Same as usual with the house tour, etc.

[HM1 VT + Entrance - let's say HM1 is called Bob]
[Sign on main door saying "Bob, Go to Diary Room"]
BB: Bob, Big Brother is setting you a secret mission. You are the only housemate to be given a secret mission. As this is a secret mission - you're fellow housemates must not discover it. If they find out, there will be severe consequenses.
[After BB has given 'Bob' his secret mission, he enters the house.]

[HM2 VT + Entrance. Let's call HM2 Betty]
[Sign on main door saying "Betty, please be quiet and go to the Diary Room"]
BB: Betty, Big Brother is setting you a secret mission. You are the only housemate to be given...

All housemates get given a secret mission.

[Last HM VT + Entrance]
[Sign on door...]
BB: Hello ??. Big Brother is giving you a secret mission. Your fellow housemates have also been given a secret mission and have each been told they are the only ones to be given one. Your secret mission is to try and discover what their secret missions are. Once you think you have discovered a HMs SM you must NOT tell your fellow HMs, you must come straight to the Diary Room to tell BB, giving full reasons why you believe this is their secret mission. You will only be allowed to guess a HMs secret mission once, so please think carefully and be as sure as possible before coming to BB.
What you fellow HMs don't know is that if their SM is discovered by yourself or a fellow HM, they will automatically face the public vote for the first eviction. If you correctly identify the SMs of eight of your fellow housemates, you will pass your task and be immune from eviction on friday.
[Final HM goes into the house and joins their fellow HMs].