Crystal Skull

Crystal Skull is the twenty first episode of the third season of Stargate SG-1.

Plot
The members of SG-1 are watching MALP telemetry of a giant Mayan ziggurat. The MALP proceeds into the ziggurat, but comes to a span which is too narrow for it to traverse. Sam pans the MALP camera across the cavern and realizes that the ziggurat contains Leptons, which means a material is slowing Neutrinos, a significant scientific find. Daniel has Sam zoom in on the object at the other end. Daniel informs them that it is a Crystal skull, identical to the one Daniel's grandfather Nicholas Ballard discovered in 1971 in Belize.

Daniel briefs SG-1, General Hammond and Doctor Fraiser on the skull that his grandfather found, explaining that his grandfather believed the skull transported him to another planet where he met aliens. His grandfather never managed to repeat the event and was scorned by the academic community. General Hammond authorizes a recon mission to the planet, but Dr Fraiser warns that she is unsure what effect the radiation caused by the Leptons might have, and recommends no more than ten to fifteen minutes exposure.

SG-1 travels to the planet and enters the ziggurat, where Carter finds high, but safe, levels of radiation. The team finds the crystal skull, which Daniel immediately becomes entranced with. Radiation levels begin to increase, and Teal'c notices a form of energy surrounding Daniel. Teal'c, unable to get Daniel's attention, fires his Zat'nik'tel at the skull. The energy dissipates, but SG-1 can no longer see Daniel, who is now unconscious. Carter warns O'Neill that the radiation levels are dangerously high before passing out. SG-1 returns to the SGC, without Daniel.

O'Neill and Carter are treated for radiation exposure while Hammond uses the MALP to scan for Daniel, but finds nothing. Teal'c, who is partially protected by his symbiote and consequently in full health, returns to retrieve the skull so that it can be studied in an attempt to learn how rescue Daniel, who they believe was teleported to an unknown location. As Teal'c removes the skull, Daniel regains consciousness and asks what has happened, but Teal'c does not hear Daniel and runs straight through him. Daniel follows Teal'c through the Stargate back to the SGC. Tests on the skull find nothing to help them locate Daniel, so Sam suggests they visit Nick Ballard. Doctor Fraiser admits she checked on Nick and found he had committed himself to a after suffering a  caused by being unable to have the skull teleport him.

SG-1 visits Ballard in the hospital. An invisible Daniel attends, encouraging his oblivious grandfather to help them. SG-1 tells him about the skull they discovered, and he asks to assist them. At SGC, Ballard is shown the skull and relives his experience for SG-1: he looked into the skull's eyes and was surrounded by a field of energy, then found himself in the ziggurat, where giant aliens, apparently composed of mist, told him


 * ''"Uy ah ual ing ual ing wetail."

He recognized this as "the enemy of my enemy is my friend" in Mayan. He closed his eyes in fear and was returned to the temple where he found the skull. The temple collapsed and he was never able to locate it again. Daniel follows Nick to the VIP quarters where Nick is staying, where he apologizes, apparently to no one. Daniel asks him what he is apologizing for, and Nick replies that it is for not adopting him when his parents were killed ("The Gamekeeper"). Daniel realizes his grandfather can hear him, but believes Daniel to be a hallucination. Daniel convinces Nick to act as a go-between and together they convince General Hammond to authorize a return mission to the planet. Nick accompanies SG-1, misinforming them that Daniel insisted on it.

Back inside the ziggurat, the skull is placed in its original position. Daniel stares into its eyes and all of the group, except Teal'c, are sent 'out of phase'. The giant 'mist' aliens appear and repeat the words Nick heard long ago. Daniel answers the giant that they are enemies of the Goa'uld. The giant is satisfied that they are friends. He remembers Nick and chooses him to stay and tell the giants about their world while SG-1 return to SGC.

Notable Quotes
O'Neill: Hey! If you'd been listening, you'd know that Nintendos pass through everything.

Daniel: I heard.

(Carter smirks)

O'Neill: ...Everything.

Teal'c: Dr. Fraiser said you are not yet fully recovered.

O'Neill: Yeah, whatever.

(O'Neill tries to stand up but instead he crashes onto the floor)

Teal'c: Dr. Fraiser is usually correct on such matters.

(Teal'c heaves O'Neill and throws him onto the bed)

O'Neill: (Muffled) Thank you.

Teal'c: You're welcome, O'Neill.

Daniel: You can see me? Why didn't you say something?

Ballard: Hallucinations always say that.

Background notes

 * It is confirmed in this episode that Daniel had (before joining the Stargate program) the theory that the Egyptian pyramids were not monumental graves for pharaohs, but landing areas for Alien space ships and he states that he lost his financial support and credibility in the international science world because of this. In the original movie, Daniel theorized only so far as that the building of the pyramids must have been much earlier than thought by most historians. He didn't mention any kind of possible Alien involvement and Aliens were only mentioned by a student in his lecture, who mocked him with the fact. The fourth season episode "The Curse" again mentioned Daniel's pre-Abydos theory about landing places for space ships, this time from Steven Rayner, a former male friend and colleague who was still upset about Daniel destroying his career by publicizing his theory, which Steven found absurd and unrealistic.