"Why are people being so unnecessarily nasty on this thread, its a bit weird."
I don't think anyone is being unnecessarily nasty. The problem is that OP's theory that Tom Cruise is trying to convert William and Catherine to Scientology is weird and not just weird but downright idiotic. Sorry if that sounds nasty, but it is an objectively idiotic (and that's putting it mildly) suggestion.
I'm not sure Cruise is even a personal friend of the Walses. They simply went to the premiere of his most recent movie because it was filmed and produced in the UK and they were supporting the British film industry.
But, let's say OP does have a point, then it's quite heroic of her/him to be warning us of the impending conversion of the next head of state to Scientology. I mean, Cruise doesn't appear to have converted any other famous person to Scientology. But, just in case he's managing to entice people as level-headed and mentally solid as William and Catherine, we should be on the lookout for traces of Scientological tenets in their behaviour and the things they say. Thanks OP for warning us of this potentially impending scandal of the conversion of the heir to the throne by Tom Cruise!
I guess Harry was right to be so dismissive of John Travolta. Travolta was clearly trying to convert Diana to Scientology when he danced with her.