Incapacitating Someone Several Levels Higher

[Draco_Lord]

So, I want to kill someone who is several levels higher then my character in game.
I am a 9th level, though when I go through the plan I will most likely be 11th level, cleric. I have the undead and resurrection domains.

What I know about him.
His will save is higher then mine. Mine is 13
He is not a spell caster
He is very perceptive
He does have items that increase his saves
And a couple of other things that are less useful.

He is the attendant of the local Lord, a young boy who he is very protective of.

I want to sacrifice him to a dark entity to become a Lich, so I kind of need him alive.

I should have his trust. Since arriving I have played nice with the Lord, befriended him even, saved he city from a band of orcs, and even inspired the Lord to become braver (back fired manipulationg but I can work with it).

So currently my plan involves convincing him to let me cast Plane Shift on him, going to the Gravity Plane, casting Geniekind and Planar Adaption on myself and flying above him, or just falling afer him if we are in the air, and then waiting for him to pass out, casting Planar Adaption on him, setting up my ritual and then doing the dark deed.

Should this plan work? Or is there some obvious chance of failure I am missing?

[Name1]

Well, there is the question of why would he want to planeshift with you and the fact that you need to cast two spells before this works.

What you could do would be offering to heal him (maybe after he's been poisoned with a nonlethal poison you prepared), but casting plane shift instead (as a non-spellcaster, it isn't likely he has the spellcraft to figure out what exactly you are currently casting). Also, you may want to planeshift to the Gravity-Plane before you enact your plan so you can cast Planar Adaption beforehand (it lasts for hours). I have to admit though, the reason I'm suggesting that is to prepare for the case that you won't have two rounds after arrival due to him attacking you.

[Draco_Lord]

Well, there is the question of why would he want to planeshift with you and the fact that you need to cast two spells before this works.

What you could do would be offering to heal him (maybe after he's been poisoned with a nonlethal poison you prepared), but casting plane shift instead (as a non-spellcaster, it isn't likely he has the spellcraft to figure out what exactly you are currently casting). Also, you may want to planeshift to the Gravity-Plane before you enact your plan so you can cast Planar Adaption beforehand (it lasts for hours). I have to admit though, the reason I'm suggesting that is to prepare for the case that you won't have two rounds after arrival due to him attacking you.

It would be a huge pain to plane shift there and back, and eat up more spells then I'd like to. I just need to surive one attack and one defensive concentration check, and I have a quickened metamagic rod, so I can cast two spells in one round. Geniekind gives me a fly speed, so avoiding him after that should be easy.