Maybe I missed this, but why is Mohinder utterly obsessed with curing Nikki, even going so far as to assist in the kidnap of Claire and ultimately the shooting of HRG...

Bearing in mind when Mohinder first met Nikki he thought she was just there to babysit him and was kinda annoyed at her being around, what has changed his tune into someone that MUST do all he can to get the cure for her?

Mohinder is worried for Niki yes but the main reason he is concerned (he has been from the start) is that the virus will spread onto the general human population and he is afraid that Niki may spread that virus. I mean look what the Shanti Virus has done one year from now, it has wiped out 93% of the population.

But how does he know that 93% of the population is killed? He can't see into the future can he?

Well, he's spent time finding people with this sickness. He knows how deadly it is. And it seems to be becoming more and more contagious as time goes on. He can't have one person with the virus running free because it WILL spread...

And I think part of him feels responsible. His sister was the first known case of the virus. Up until very recently, his blood was full of the antibodies that could cure it. Whether he likes it or not, he's connected to the virus in the most base of ways and the good in him wants to do everything he can to stop its spreading.

This 'good in him' allows him to kidnap and murder...

For what he sees as the 'greater good'. No one is perfect. He's only doing what he feels he has to do in order to stop the virus.

Personally, I think HRG and Mohinder planned HRG's 'death' all along. It shows Bob that Mohinder is really on his side.

Mohinder's been predicting disaster from the virus since he was aware that the Company had it. In fact I believe he's mentioned it every single episode he's been in so far in season 2, along with the words "incurable strain" and "cross over to the general population." Well we already know the incurable part has come to pass, so it's hardly surprising that he expects the crossing over imminently. So no, he doesn't know what Peter knows, but it doesn't take a genius to see it coming. This is, after all, his field of study; and whatever you say about how well (or rather poorly) Mohinder reads people, he's proven his intelligence when it comes to genetics.

In light of that it's fairly safe to assume that he chose the general population over HRG, not just Niki. Or at least, that's what he thought he chose. Short of him saying "I can't let the virus cross over," right after the shooting scene - and incurring the righteous wrath of more fans at inept writing - I can't really see a way to tie the two more firmly together.

Poor guy =/

I like that theory.