Tomb Raider: Underworld

The story begins in medias res; Lara Croft navigates her home Croft Manor after an explosion, then is shot at by her tech assistant Zip. One week earlier, Lara is investigating a sunken island in the Mediterranean Sea as part of her search for Avalon, hoping it will lead her to an explanation for the disappearance of her mother Amelia and salvage her father Richard's academic reputation despite the scepticism of Zip and her research assistant Alister. The island houses ruins dubbed "Niflheim", one of the many Norse underworlds, and Lara discovers one of the gauntlets attributed to the god Thor to wield Mjolnir. While ambushed by mercenaries sent by rival Amanda Evert, Lara recovers the gauntlet, which has shaped itself to her hand. On Amanda's ship she also meets an imprisoned Jacqueline Natla, former ruler of Atlantis presumed dead after their last encounter. Natla reveals that Amelia was sent to "Helhiem"−another name for Avalon−and directs Lara to ruins in Thailand, hinting that her father also searched for Mjolnir before she is taken by Amanda as the ship sinks due to an explosion caused by the mercenary leader who ambushed Lara.
In Thailand, Lara navigates the ruins of "Bhogavati" and finds more ancient ruins that housed a gauntlet; Richard was sent there by Natla, but removed the gauntlet and destroyed a map showing the location of Thor's relics. From the use of his initials referencing her grandfather, Lara deduces that Richard hid the gauntlet in Croft Manor. Finding Richard's study in Croft Manor's catacombs, Lara finds the gauntlet and a tape-recorded message from Richard, revealing Helheim contained a powerful weapon and that he destroyed the map after recording it to prevent its use. She also encounters a pair of Thralls, undead guardians of Thor's relics created from eitr. Croft Manor is bombed, and Lara learns from Zip that the bomber, who looked identical to her, stole the magical stone Amanda used during Legend. Lara then encounters a Doppelgänger—a being modelled to look like Lara—who shoots Alister and flees; despite Zip's protests, Lara continues her quest so she can use Mjolnir to kill Natla. In the ruins of "Xibalba" in Mexico, Lara finds both Thor's belt−which powers the gauntlets and is protected by more Thralls−and ancient carvings detailing the myth of Jörmungandr, who will flood the world before fighting Thor, with both dying. In the ruin of "Valhalla" on Jan Mayen, Lara recovers Mjolnir, then confronts Natla.
Natla provides Lara with the coordinates of Helheim, but points out that only she knows the ritual to prepare its gates, so Lara reluctantly strikes a bargain and frees her from her cell. Amanda attempts to stop her, but the Doppelgänger attacks and apparently kills Amanda. Lara dives to the ruins of Helheim under the Arctic Sea, and with Natla's preparation opens its entrance with Mjolnir. Lara then discovers Amelia is turned into a Thrall and is forced to shoot her. Natla appears and reveals that she killed Richard after his betrayal in Thailand, then sets the Doppelgänger on Lara before leaving to awaken Jörmungandr, revealed as a metaphor for the Earth's faultlines; Natla intends to activate an ancient device above the faultlines' weakpoint and trigger apocalyptic volcanic activity. Amanda appears and apparently throws the Doppelgänger to its death, allying with Lara to stop Natla's plan. Lara finds the device and destabilises it, then throws Mjolnir at Natla, knocking her into a lake of eitr. Lara and Amanda then use the chamber's dais travel device, escaping to the Nepalese monastery where Amelia first disappeared. Amanda tries to restart their fight, but backs down and leaves when Lara refuses; before she leaves, Lara bids goodbye to her mother.
The downloadable content episodes "Beneath the Ashes" and "Lara's Shadow" are set after these events. The Doppelgänger, revealed to have survived, finds a disfigured Natla and is compelled through the magical command "Okh Eshivar" to take her to the Doppelgänger's birthplace in an ancient ruin. After the Doppelgänger restores the ruin's healing technology, Natla orders the Doppelgänger to kill Lara then itself. At Croft Manor, Lara finds notes on a Thrall-creating stone carved with the "Okh Eshivar" command. After a Thrall attacks from a cavern, she descends deeper into the catacombs and finds the stone. The Doppelgänger then attacks, and Lara uses the command phrase bringing the Doppelgänger under her control. After Lara questions the Doppelgänger's nature and the Doppelgänger states that they are both driven by something beyond their control−compulsion for the Doppelgänger and obsession for Lara−Lara frees the Doppelgänger from all commands and sends it back to Natla as a means of avenging Alister. Back at the ruin, the Doppelgänger destroys the device, then watches as a trapped Natla is drowned in a rising pool of eitr.