Sheena is a main character in Arceus and the Jewel of Life. She has been entrusted with the job of keeping the Michina Ruins hidden from the outside world, and alongside her partner Kevin strive to achieve peace. Sheena also has a unique ability to see into the hearts of Pokémon.
After the events taking place at Alamos Town, both Sheena and Kevin became aware of the spacial displacement occurring, and were present when the town was returned to its appropriate location.
Befriending Ash, Dawn and Brock
When a giant whirlpool appeared, she and Kevin ran to the lake where Ash and his friends are. When Ash's Pikachu and Dawn's Piplup were sucked into the whirlpool, she calls for Dialga to save them which he does. Then, Giratina appears and attacks Diagla. She tries to connect it with its heart but the Pokémon's rage is too strong and Ash calms Giratina down. Sheena then introduces herself and tells them about her power. Brock flirts with her but is knocked out by Croagunk. Then, another whirlpool appears and traps Dialga but is saved by Palkia which she thanks. In the ruins, she and Kevin show them the Time-Space Axis that shows their world, the Reverse World, Diagla's dimension, Palkia's dimension and Arceus' dimension. Then, she shows the legend of Arceus and her ancestor, Damos. She shows them the Jewel of Life and says that they must return the Jewel to Arceus.
When Arceus appears, Sheena apologizes for Damos' despicable actions and returns the Jewel to him but he stomps and says that it's fake. Sheena, who's surprised, tries to explain to Arceus but his rage is too strong. Then, the Dragon Trio appear and try to stop Arceus. Dialga sends Sheena, Ash, Dawn, and Brock to the past when Arceus was betrayed. In the ruins, they almost fall to their deaths when Arceus attacks but Dialga sends them several hours before the betrayal. Marcus appears, uses Hypnosis on the kids, and tells Sheena to come with so she can explain everything to him. He gives her the staff but not with the Jewel which finds out when she's with Arceus. The Pokémon attack Arceus, Sheena tries to stop them but is saved by Damos who almost falls to her death. Sheena and Damos are almost killed by the "silver water" but Brock's Sudowoodo uses Hammer Arm to stop it.
Damos and Sheena manage to stop the Pokémon from attacking but Sheena loses control while tring to calm Arceus and leaves Damos to calm him. Arceus is dying from the attacks and Sheena and rest of the gang began to disappear. Damos calms Arceus down, the Jewel has been returned and the gang doesn't vanish. Before Sheena and her friends could fall to their deaths, Arceus saves them including the Pokémon. When they return to the present, they see the Dragon Trio injured and Arceus prepares the final attack but Ash reminds him what they fixed in the past. Everything is back to normal and Sheena falls in love with Kevin. They see a carving that Damos made for them which Sheena makes happy who realizes the true person inside her ancestor.
Much like Damos, Sheena possesses the same ability to read the hearts of Pokémon. They both use the incantation "Transcend the Boundaries of Space and Time".