Odyssey, a human-designed interstellar spacecraft that incorporates alien technologies, is the second of the BC-304 class vessels to be built, following her sister ship, the Daedalus. Because the advanced alien technologies were integrated into the original design rather than tacked on after the fact, Odyssey has several advantages over her BC-303 predecessor, the Prometheus.

Odyssey uses both sublight engines and a powerful hyperdrive that makes it capable of intergalactic travel. Most of the systems rely on crystals both for programming and as a power source. The ship is capable of landing or of remaining in planetary orbit, and the inertial dampeners and artificial gravity limit the effect of G-forces and zero gravity. It is equipped with a ring transporter, and its weapons include missiles and rail guns. The ship carries F-302 fighter craft for aerial combat, and the hangar bay uses a force field that allows the bay to remain pressurized as the F-302s enter and leave. Odyssey also uses several Asgard technologies, including shields, sensors, and the transport beam, and an Asgard control panel uses Asgard stones to control several other major functions of the ship such as power distribution, navigation, weapons, and life support. The Odyssey is a Deep Space Carrier, and the patch worn by its crew indicates "U.S.S. Odyssey" across the top, "Deep Space Carrier" across the bottom, and at the center is an image of the ship in a starfield with the registry number "PB3865."

Odyssey was nearing completion when the Prometheus was destroyed at Tegalus. Shortly afterward, with 90% of its primary systems operational, Odyssey embarked on its shakedown cruise under the command of Colonel Paul Emerson, however it was called into action to rescue SG-1 from P6G-452 where they had been captured by members of the Lucian Alliance. SG-1 had recently been implanted with subcutaneous transmitters, eliminating the need for a locator beacon to target the Asgard transport beam, and Odyssey was able to extract SG-1 just as they were about to be killed. The mission also led Odyssey and SG-1 to encounter Ba'al's mothership, from which he had been stealing stargates, and in a confrontation with Ba'al and the Lucian Alliance, Odyssey recovered the stolen stargates and escaped into hyperspace with minimal damage.

Because the Daedalus was most often used for missions to and within the Pegasus Galaxy, Odyssey became Earth's main interstellar defense in this galaxy. When carnivorous insects known as R75 overran the Gamma Site, Odyssey was sent to the planet per protocol CR91 to deliver a payload of lethal toxin from orbit. The ship successfully beamed aboard SG-1 and representatives of the IOA in the last seconds before the toxin was deployed.

Under the command of Colonel Emerson, Odyssey also joined the Korolev and an armada of Jaffa, Tok'ra, Asgard, and Lucian ships at the supergate near P3Y-229 as the Ori warships began their invasion of the galaxy. The Asgard Kvasir cooperated with Carter aboard the ship to search for a way to prevent the Ori from dialing the gate, but when the supergate activated, the battle against the Ori warships began. Odyssey sustained major damage during the battle, and systems including communications, hyperdrive, and beaming capabilities were non-operational. Nevertheless, Mitchell was able to rescue Carter, who was stranded in space during an EVA, by performing a delicate maneuver with the sublight engines to scoop her into the hangar bay. Once repairs had been made, Odyssey pursued SG-1 to Chulak and beamed the team aboard before retreating into hyperspace.

A bold plan, designed to block the Ori supergate by causing a wormhole arc from a black hole, sent Colonel Emerson and the Odyssey to Atlantis in the Pegasus Galaxy. Rodney McKay cooperated with Carter and Mitchell aboard the Odyssey as they deposited a stargate near the accretion disk of a black hole and attempted to beam shaped charge warheads near the gate to cause a wormhole to jump to the supergate. There the Odyssey also came under attack from a Wraith hive ship, but in a successful mission, the shaped charges not only caused the wormhole to arc, but also destroyed the Wraith ship.

In the battle against the Ori, the Jaffa High Council targeted Ori worlds using the Ancient weapon of Dakara, and SG-1, on a mission to one such world, was beamed aboard Odyssey just as the energy wave approached their position. They failed to commandeer the Ori warship that was left behind, but when Adria piloted the ship to Dakara with SG-1 aboard, Odyssey once again beamed the team to safety as Dakara was destroyed.

Anateo, a former lieutenant of the Lucian Alliance, used false intelligence to draw Odyssey into an ambush with the intention of capturing SG-1 in a move that would assure his succession to the leadership of the Alliance. The signal of Odyssey's emergency transponder, or subspace beacon, lured Daniel and Vala to the ship, where they joined Carter and the crew as Anateo's hostages. They succeeded in retaking the ship, however, by beaming Anateo into space and detaining their Lucian captors, but during the capture of the Odyssey, Colonel Paul Emerson was shot and killed on Anateo's orders.

When Daniel was captured by Adria and transformed into a Prior, the Odyssey was used as a secure base of operations to capture and detain Daniel, using an anti-Prior device to neutralize his Ori-given powers. Daniel overcame the device, however, and used the Odyssey as part of his plan to complete the construction of Merlin's weapon and to deliver it through the supergate to the Ori galaxy. With O'Neill aboard, the Odyssey stood ready to order that the wormhole to the Pegasus Galaxy be shut down and to return SG-1 to safety as the Ori ship carrying the device entered the supergate. Odyssey was able to approach Adria's warship undetected because Daniel had used a ZPM and his powers as a Prior to cloak the ship.

As Earth faced the threat of an attack by Arkad's Jaffa, Odyssey delivered SG-1 to Arkad's world, where they attempted to prevent Teal'c from seeking his revenge. Odyssey was also ordered to verify Jacek's information that cargo ships of naquadah remained poised to carry out Arkad's attack, and from orbit, Odyssey launched missiles that destroyed the ships of naquadah in a massive explosion.

Following the death of Colonel Emerson, Colonel Davidson took command of the Odyssey. With Colonel Davidson at the helm, Odyssey participated in the mission to capture Adria. Once again the ship remained cloaked as it approached Ba'al's mothership where Adria was being held prisoner. From there, SG-1 beamed aboard Ba'al's ship to recapture the Orici, and aboard the Odyssey, surgery was performed to remove Ba'al's symbiote from Adria's host body, surgery that would bring Adria to the brink of death and lead to her ascension.

As the Asgard faced their demise as a race, the Odyssey became their legacy. At the invitation of the Asgard, General Landry commanded the Odyssey on its mission to the Asgard homeworld of Orilla. There the Asgard offered their final gift to the humans of Earth by sharing all their knowledge and technology. Aboard the Odyssey, the Asgard installed a new Asgard computer core that was equipped with its own power source that would not infringe on the ship's ZPM, but which would be fully integrated into all the ship's systems once the upgrades were complete. Asgard control panels using Asgard stones made it possible to interface with the core by communicating with a holographic representation of Thor or any Asgard in the knowledge base. The upgrades also included massively superior weapons and shields, and time dilation field technology built directly into the core.

Inexplicably, however, the Asgard upgrades seemed to be responsible for allowing Ori warships to track the Odyssey, even through hyperspace. Odyssey's new Asgard shields withstood an Ori attack far better than its previous defenses, and the new Asgard energy weapons, which fired a bluish beam, were capable of destroying an Ori warship. Nevertheless, as Odyssey returned from Orilla, it was pursued by Ori ships, and because the ship came under attack each time it emerged from hyperspace, Carter was unable to isolate the Asgard core from the hyperdrive controls to prevent the ship from being traced.

At P3X-474, Odyssey dropped out of hyperspace to beam the crew to the planet's surface, from which they could gate home. Only Landry and SG-1 remained aboard in an attempt to engage the Ori and preserve the ship. As the Ori weapons fire threatened to destroy the Odyssey, Carter activated the time dilation technology, creating a time dilation bubble around the ship which seemed to freeze the Ori weapon in time. Carter had hoped to use phase-shift technology to take the ship out of phase, allowing the weapons fire to pass harmlessly through the ship, however the design of the ship's systems made this impossible. Instead the team became trapped in time aboard the ship, able to survive by creating necessities including food, water, and oxygen by using a matter converter that Carter had modified. For more than 50 years the team was unable to reconcile the discrepancy in time and energy that prevented them from taking the ship out of phase, until finally an alternate solution was discovered. By allowing the Ori weapon to strike the ship, and channeling its energy through the ship's systems, Carter was able to reverse time within the bubble, and sever the connection to the computer core. Odyssey and its crew were returned to the point in time of the battle, and they escaped into hyperspace, no longer pursued by the Ori. The Odyssey was spared, and the legacy of the Asgard was preserved.

Cross Reference: Anateo, Asgard, Asgard Stones, Asgard Transport Beam, Atlantis, BC-304, Black Hole, Crystals, Daedalus, Colonel Davidson, Paul Emerson, F-302, Force Field, Gamma Site, Hive Ship, Hyperspace, Kvasir, Locator Beacon, Lucian Alliance, Major Marks, Ori Warship, Orilla, P3X-474, P6G-452, Pegasus Galaxy, Prometheus, Protocol CR91, Mark Stern, Subcutaneous Transmitter, Supergate, Time Dilation Bubble, Catherine Womack, Wraith, Zero Point Module

Episode Reference: Off the Grid, The Scourge, Camelot, Flesh and Blood, The Pegasus Project, Counterstrike, Company of Thieves, The Shroud, Talion, Family Ties, Dominion, Unending