The Search for Halsey

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The Search for Halsey
EP9 CH1 The Search for Halsey.png


Halo 4

File name (?):



Spartan (Fireteam Crimson)




"Cyclone," Requiem


Investigate Halsey's transmission


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Jul 'Mdama has abducted Dr. Catherine Halsey. All fireteams dispatched to investigate her whereabouts.

The Search for Halsey is the first chapter of Spartan Ops' ninth episode, Key.[2]


In the wake of Doctor Catherine Halsey's abduction by Jul 'Mdama, all Spartan Fireteams have been reassigned to recover her. Fireteam Crimson is sent to "Cyclone" in hopes of tracing a transmission made by Halsey. They are assisted by Doctor Lani Truman from Infinity Science.

After Crimson takes out the Covenant guarding the area, Truman sends the Spartans to a specific structure containing a Covenant comm terminal. To their surprise, the structure's door opens for them. Crimson takes out the Hunters and Elites inside and accesses the comm terminal. From it, they learn that Jul 'Mdama has ordered all Covenant forces to meet at a place called "Librarian's Rest". Roland, meanwhile, tracks down where Halsey's transmission was sent to next. It's in an area already occupied by Marines.

While Truman attempts to trace the rest of Halsey's transmissions in hopes of determining where "Librarian's Rest" is located, Miller sends Crimson to investigate a sudden power spike at another structure. On the way to investigate, the Spartans come under attack by Promethean forces. Crimson fends off the Prometheans and finds a control console where the energy spike apparently originated from. They are unable to determine its purpose, but Roland notes that the terminal and Halsey's encrypted comm stream are using the same modulation frequency, indicating they are connected somehow.

Just then another wave of Prometheans attacks Crimson's location. Unexpectedly, some friendly beam turrets are activated and assist Crimson in the fight. A group of Sentinels also comes to Crimson's aid. Furthermore, an unidentified presence inside the system assists Truman in decrypting Halsey's transmissions. The decryption stops at 99%, and at the same time the terminal's modulation frequency also stops. On a hunch, Miller orders Crimson to activate the terminal. This generates a massive data stream from a nearby tower, but Truman can't analyze it properly.

Miller orders Crimson to head to the area where Roland has determined Halsey's transmission was relayed to next.


All dialogue is spoken through the COM.


Opening shot: Multiple Pelicans depart from the UNSC Infinity and at least three Vindication-class light battleships and descend on Requiem.

Cut to "Cyclone" on Requiem. Fireteam Crimson’s Pelican approaches.

  • Commander Sarah Palmer: “Infinity Commander Sarah Palmer to all Spartans. Doctor Catherine Halsey has been abducted by Jul ‘Mdama’s forces. Every fireteam is being reassigned to find her. Good luck and good hunting. Palmer out.”

Crimson’s Pelican lands at "Cyclone."


  • Spartan Jared Miller: “Crimson, Dr. Halsey was relaying transmissions through this location before she was snatched. You’re here to help trace the call.”
  • Miller: “Spartan Miller to Dr. Truman.”
  • Miller: “Doc, I got a team of Spartans on location. You have those coordinates ready?”
  • Truman: “Yes. Sending them to you now.”
  • Miller: “Clear that position, Crimson.”

Crimson engages Covenant forces nearby.

  • Miller: “Thanks, Dalton.”

A Covenant Phantom descends and deploys enemy reinforcements.

Once most Covenant troops are killed:

  • Miller: “Mop up the last of them.”

Once all the Covenant are defeated:

  • Miller: “Area secure. What are we looking for, Dr. Truman?”
  • Truman: “It’s behind those doors.”

Waypoint appears on HUD.

Crimson moves in to investigate the structure. Upon reaching the door Truman directed them to, it dissolves. A Hunter emerges from the structure.

  • Miller: “That’s... odd.”
  • Truman: “Indeed. As if the structure is responding to Crimson.”

Crimson kills the Hunter and enters the building. More Covenant are waiting inside including a second Hunter.

  • Miller: “Take ‘em out!”

Crimson clears out the structure.

  • Miller: “Dr. Truman. Which of these devices is the comm relay you’re after?”
  • Truman: “Right here, Crimson.”

A terminal is marked. Crimson activates it. They hear a transmission spoken in Sangheili:

  • Sangheili voice: "Dieduckt gahkaboonoh Liebuh-Rahrian musuyano. Kaboonzaywah wohchita kneekohsoh woorumahtwo."

Roland translates for them.

  • UNSC AI Roland: “A call to arms. ‘Mdama wants everyone to meet at "Librarian's Rest," but doesn’t include coordinates.”
  • Truman: “Hmmm... Not familiar with it.”
  • Roland: “You want I should take a look at these comm logs? I could track Dr. Halsey’s transmissions through this system.”
  • Miller: “Have at it, Roland.”
  • Roland: “Got it! I know where Halsey’s call was routed next. Some Marines are near that location right now.”
  • Truman: “I might be able to track down Dr. Halsey’s transmission through here, and give us a hint as to the location of "Librarian's Rest.”
  • Miller: “Have at it, Doc.”
  • Miller: “Crimson! There’s a sudden power spike nearby. Marking it for you now. Let’s go get a look.”

Crimson heads off to investigate. As they approach their objective, Prometheans suddenly phase onto the battlefield.

  • Miller: “Prometheans!”

Crimson battle and defeat the Prometheans. They move into an opening in the structure and discover a terminal crackling with energy.

  • Miller: “Crimson. There’s the source of the power spike. Dr. Truman, any thoughts?”
  • Truman: “No idea why it would suddenly activate, no.”
  • Roland: “Hey, uh, Doc? You probably can’t see it, what with your boring biological eyeballs and all, but that power source is modulating at a frequency matching the encryption key on the comm stream you’re trying to crack.”
  • Miller: “Roland, don’t be rude.”
  • Truman: “He’s right though... It’s almost as if they’re connected. I’m going to take a closer look at this.”

New enemy contacts appear.

  • Miller: “Prometheans! Everywhere! Hold position, Spartans! Fend them off!”

Crimson engages the Prometheans once again. Several beam turrets materialize around the structure and begin firing upon the Prometheans.

  • Miller: “Crimson, what did you do? Why did those turrets just come online?”
  • Roland: “Crimson didn’t do anything.”
  • Miller: “And they’re shooting the bad guys instead of us? That’s... new.”

If one of the allied defense turrets is disabled:

  • Miller: “Defense turret down but not destroyed. You should be able to reactivate it.”

During the middle of the battle:

  • Miller: “Dr. Truman, any luck?”
  • Truman: “Hmmm... This is odd. It looks like someone is trying to help me decrypt the comm stream.”
  • Miller: “Roland? Are you helping Dr. Truman?”
  • Roland: “Nope. But she’s right. There’s a secondary encryption cracker working from the inside out. Something is definitely helping her along.”
  • Miller: “Keep an eye on it for me, Roland.”
  • Roland: “Will do.”

Once the area is clear:

  • Truman: “Spartan Miller, the encryption is ninety-nine percent cracked.”
  • Miller: “How long till you’re done?”
  • Truman: “Huh. It’s stuck at ninety-nine. But the frequency modulation that Roland identified is stalled as well.”

A new wave of Promethean Watchers and Crawlers attack Crimson. A flock of Aggressor Sentinels unexpectedly come to the Spartans’ aid.

  • Miller: “Crimson, I think the Sentinels are helping you.”

The combined power of Crimson, the Sentinels, and the beam turrets make short work of the Promethean attackers.

  • Roland: “Doc, what do you think would happen if Crimson flips that breaker there and opens up that power source?”
  • Miller: “Is that wise?”
  • Roland: “Sure. Why not?”

Crimson activates the power source. The Sentinels start flying away.

  • Miller: “Where are they going?”

The Sentinels surround a tower and begin zapping it with their beams. The tower unfolds and emits a massive horizontal beam of light through a row of ring-like structures.

  • Miller: “Dr. Truman! Analysis?”
  • Truman: “Massive energy output. It’s a data stream, but too fast to analyze.”
  • Miller: “Roland, what about our trace on the Halsey comms?”
  • Roland: “Good to go any time. Boa Squad’s ready and waiting for Crimson’s help.”
  • Miller: “Tell the Marines Crimson are inbound. Spartans, get to the LZ. Let’s see where this trace leads us.”
  • Miller: “Crimson, prep for pickup.”

Crimson heads to the LZ and is picked up by a Pelican.


Level ends.


  1. ^ Halo 4 Editing Kit, game file H4EK\tags\levels\dlc\dlc_variant_tags\e9_m1_vortex_traces.gameenginefirefightvarianttag
  2. ^ Halo Waypoint - Spartan Ops menu.