Who???

Was interrogating Halsey in Halo 4?

Any clues, ideas or thoeries?

Other than highly likely being someone involved with the S-IV’s, it doesn’t seem like its anyone we know.

Well I can tell you an idea where this goes in Halo Canon.
It happens on Ivanoff Station. Which means its about March 2553.

Now the only things I can think of at the moment is either if it happens before Parangosky speaks to her in Chapter 18 of Grasslands or after that.

Hints that it is before is Halseys Quote in the game “What does John have to do with this? …you want to replace him.”. Meaning she doesn’t know about the Spartan 4’s yet.
She is told by Parangosky in the book. “Yes, another project you were never told about”.

Though info that insists otherwise is Halsey knowing about Master Chief being MIA. In the book “She wondered how much they’d found to say about John-117”
Yet in the game Halsey says “His file reads ‘Missing in Action’.”
Though Halsey could have had plenty time to read his file before Parangosky interrogates her, and is just curious to what they found.
There is the quote “you already know everything.” meaning that lots of interrogations have already happened.

With all this in mind. The quote “What are you after? The others before you were Naval Intelligence but you… you’re something else.” could mean hes more of a lackie of Parangosky, or as UrbaneRocket495 says someone involved with the S-IV’s. Getting info or something to assist Parangosky. Or info that could assist the advancement of the S-IV’s.

I more side with the S-IV idea, as that seems to be what the whole interrogation is about. But giving all possible ideas seems like a good idea.

I’m probably wrong here but wasn’t Ackerson supposed to head the Spartan IV program like he did the Spartan III program? He had to be replaced however because of his death. The interrogator could be the head of the Spartan IV program, or definitely someone involved with it as others said before. The conversation was mainly about ways in which the Spartan IVs could be improved e.g. “You think your Spartan’s lack of basic humanity helped?”, “What are you after?”.

The only problem with him being from the Spartan-IV program is that the Spartan-IVs, or at least some of them, were already created and deployed by the time Halsey was arrested. So what exactly is he trying to get from Halsey when the Spartan-IVs already exist? Improvements perhaps? Maybe he simply wanted another John-117? He wants to learn what Halsey saw in John so they can find other candidates who fit the profile and they can make a literal replacement?

Wouldn’t it be interesting if that was what Thorne was for?

Probably improvements on another batch of IVs, or maybe another Spartan program entirely.

Could be possible, they did seem especially interested in John, probably because of his actions between Halo: CE and his disappearance at the end of Halo 3. Besides being the squad leader of the Spartan IIs I imagine he wouldn’t have been very distinguished as he was average amongst the IIs. His status as squad leader and actions after the fall of Reach probably piqued their interest. He did after all, prevent the extinction of the human race.

I think that the man interrogating Halsey is one of the people who interrogated John and a couple others about a mission on Sigma Octanus IV in The Fall of Reach(novel).

> The only problem with him being from the Spartan-IV program is that the Spartan-IVs, or at least some of them, were already created and deployed by the time Halsey was arrested. So what exactly is he trying to get from Halsey when the Spartan-IVs already exist? Improvements perhaps? Maybe he simply wanted another John-117? He wants to learn what Halsey saw in John so they can find other candidates who fit the profile and they can make a literal replacement?
>
> Wouldn’t it be interesting if that was what Thorne was for?

He wanted to know if the Spartan-IIs were effective because they were broken, so perhaps whoever runs the Spartan-IV programs wants to either break recruits or find soldiers with angsty backstories in the hope that they will be better soldiers.

> > The only problem with him being from the Spartan-IV program is that the Spartan-IVs, or at least some of them, were already created and deployed by the time Halsey was arrested. So what exactly is he trying to get from Halsey when the Spartan-IVs already exist? Improvements perhaps? Maybe he simply wanted another John-117? He wants to learn what Halsey saw in John so they can find other candidates who fit the profile and they can make a literal replacement?
> >
> > Wouldn’t it be interesting if that was what Thorne was for?
>
> He wanted to know if the Spartan-IIs were effective because they were broken, so perhaps whoever runs the Spartan-IV programs wants to either break recruits or find soldiers with angsty backstories in the hope that they will be better soldiers.

They weren’t broken at all. They just had a different mindset “Records show Spartans routinely showed mildly sociopathic tendencies”. They were able to kill their enemies without feeling guilt, could control and stow away their emotions without bursting out or showing any signs of frustration or anger and struggled to form social relationships with anyone other than their fellow Spartans (Except for Kurt who was very sociable and routinely made friends with the DIs, which unnerved the others). Anyone brought up in the same environment as them would display the same behaviour. To call them “Broken” implies that they’re beyond functioning.