|This article is about a/an two-part episode in Power Rangers Dino Thunder.|
Mesogog's lair was destroyed with Mesogog still inside but it's not time to celebrate yet. An enraged Zeltrax declares war on the rangers like never before and holds Elsa hostage. To make things worse, Cassidy and Devin know their true identities and intend to use it to their advantage. It'll take all that the rangers have to defeat Zeltrax and end it once and for all and keep from being exposed for what they really are.
Mesogog tortures Anton Mercer as he prepares to unleash his master plan. He activates a powerful cannon that is designed to transform all humans into dinosaurs. Meanwhile, Trent observes all of this in secret to get information on Mesogog's plan for Tommy and Hayley. Meanwhile, the other Rangers talk about the prom. Conner goes through his list of potential dates, while Ethan doesn't plan to go and Kira doesn't seem to concerned. Meanwhile, Devin plans to ask Cassidy to the prom, but Cassidy informs them that they have to find the identities of the Power Rangers right away or they're fired. Mesogog needs an incredible amount of energy to power his cannon, which is why plans to get the Dino Gems, but ensures he has enough by draining the power that he gave Elsa. Trent confronts Mesogog about releasing his father and promises to get him the Dino Gems for an exchange. Elsa finds herself on top of a building, but is soon found by Zeltrax who is seeking his ultimate revenge. Ethan is in line to get tickets for Asteroid Conquest 2 when he called into action. As he runs off, he doesn't realize that someone is listening. The Rangers rush to stop Zeltrax who they spotted going after a woman they don't realize is Elsa. As the Rangers morph into action, Devin who was in the alien costume has followed Ethan and is filming the entire thing. Conner, as Triassic Ranger activates the Battlizer and takes down Zeltrax, but he escapes before the blast. Meanwhile, Tommy rushes in to save the woman and discovers that she is Elsa is now free from her brainwashing. As the Rangers rush Elsa back to the Dino Lab, Zeltrax follows them and discovers their secret location. Trent informs the other Rangers of Mesogog's plan and says giving him the Dino Gems is the only chance that they have of getting in to stop him. As Trent goes to open an invisiportal, Hayley presents the Triceramax Command Center - an armed vehicle designed to take down Mesogog's Island Fortress. Trent confronts Mesogog and demands that he release his father, but Mesogog can't be trusted and sends Trent to the floor with his mind attack. Trent is able to open the invisiportal just in time for the other Rangers to make it through. The Rangers and Hayley arrive on the island, and are confronted by the Tyrannodrones. The Rangers take them on as Hayley goes after the cannon. As the Triceramax heads to take down the cannon with its laser, the Tyrannodrones interfere with the beam, but Conner comes to the rescue. Hayley uses the Triceramax Command Center's laser to destroy the cannon and inflict heavy damage upon the Island Fortress. Mesogog gets caught in the collapse of the Island Fortress as his machine overloads. Trent retrieves the Dino Gems and rescues his father. The Rangers have no time to wait for Trent and have to hope he finds his own way out. Trent and Anton make it out just in time with the Dino Gems intact. Meanwhile, Zeltrax invades the Dino Lab and kidnaps Elsa, leaving the Lab in ruins.
The Rangers return to find the Dino Lab demolished and Elsa missing. They check the black box to find out that Zeltrax is responsible. Not long after, they show up as Zeltrax unleashes his powerful Zelzord to attack Reefside. Zeltrax holds Elsa captive inside the Zelzord as she tries to talk some sense into him. Tommy invades the Zelzord to save Elsa and stop Zeltrax once and for all, but he runs into the Triptoids. Meanwhile as Trent fights the Triptoids on the ground, the other Rangers use their Megazords to confront the Zelzord. Kira rushes off to help Tommy and they both come to Elsa's rescue, but Zeltrax won't let them go without a fight. Zeltrax powers up into his ultimate form, but Tommy and Kira are still finally able to destroy him. Zelzord however remains too powerful for the Thundersaurus and Mezodon Megazords to stop on their own. Tommy instructs them to summon all of the Dinozords to stop Zelzord, but they must ultimately sacrifice the Dinozords before they are all destroyed. Conner and Ethan do it and barely make out alive, but it can't be over yet, can it? Mesogog has survived and has absorbed enough energy from the Dino Gems to become a powerful monster. "Dino Thunder, Power Up!" the Rangers call out as they morph into action one last time to take down Mesomonster. Mesomonster is too powerful for even the Battlizer and his DNA copies itself to make clones and four times the trouble. The Power Rangers must summon all of their power from their Dino Gems to unleash an unstoppable power. The Dino Gem power becomes a giant dinosaur of energy which devours Mesomonster and all of his clones. The Power Rangers Dino Thunder pose victoriously as Mesogog is destroyed once and for all. The Rangers used all of their Dino Gem power to destroy Mesogog and they have returned to normal with their Gems as no more than artifacts. Cassidy and Devin have been taping the entire battle and know their secret identities, but have decided to give up the tape, because of their friendship. Tommy reminds the others that their lives may go back to normal, but they'll never be the same. Devin and Cassidy show up at the prom together. Conner arrives there with Krista, the "tree girl", because it's what's on the inside that counts. Ethan brings Angela a girl he met standing in line for tickets to Asteroid Conquest 2. Trent reveals that he will be going to art school in the fall, and Tommy has decided to live the quiet life, but we all know how that usually goes. Elsa has taken over the position as the new principal, and Anton asks her for a dance with an old friend. Tommy goes to the stage to introduce the band and gives everyone props for all they've been through during the year. Kira is introduced and sings as everyone enjoys the dance and memories are shared.
- James Napier as Conner McKnight (Red Dino Thunder Ranger)
- Kevin Duhaney as Ethan James (Blue Dino Thunder Ranger)
- Emma Lahana as Kira Ford (Yellow Dino Thunder Ranger)
- Jason David Frank as Tommy Oliver (Black Dino Thunder Ranger)
- Jeffrey Parazzo as Trent Fernandez (White Dino Thunder Ranger)
- Ismay Johnston as Hayley Ziktor
- Tom Hern as Devin Del Valle
- Katrina Devine as Cassidy Cornell
- Latham Gaines as Mesogog (voice) & Anton Mercer
- Miriama Smith as Elsa
- James Gaylyn as Zeltrax (voice)
- Hannah Banks as Angela (as Hannah Tolich)
- George Port as Guy
- Antonia Prebble as Krista
- Thundersaurus Megazord
- Mezodon Megazord
- Trent's morphing call is different in this episode, in which it was "White Ranger, Dino Power". However, in this episode he uses the same call as Conner, Ethan, Kira & Tommy, "Dino Thunder, Power Up" in Part 1.
- This is the only episode that includes the Triceramax Command Center which was designed specifically for the purpose of taking down Mesogog's Island Fortress.
- Conner calls for 'all' the Dinozords, however the Dragozord isn't shown with the others. This is because, in Abaranger, the Dragozord's Sentai counterpart had already been destroyed by this point in the series.
- The Rangers defeat Mesogog by combining and sacrificing their powers to form a powerful attack. A similar actions takes place in the Great Legend War of Kaizoku Sentai Gokaiger, but on a far larger scale, with all the past 34 Super Sentai teams sacrificing their powers to defeat the invasion fleet of Space Empire Zangyack.
- When the Rangers are not sure whether Trent and his father have survived, Ethan says "It's not like they're going to fall from the sky and land in front of us", to which Kira is responding in anger. In "Day of the Dino: Part 2", Ethan said the same thing when he, Conner and Tommy were looking for her and she literally did land on the hood of Tommy's car via an invisiportal. That's why Ethan responded with "Last time I did that, it worked".
- This episodes title is a reference to the AC/DC song "Thunderstruck."
- This is the last time that Tommy has an unmorphed appearance before Legendary Battle.
- This is the last episode with 2 words in the title, before Broken Spell.
- The Triceramax Command Center Truck is summoned using a device that includes a Power Morpher.
- The command truck that the rangers are in to travel to Mesogog's island is the same truck used in Power Rangers Ninja Storm but repainted.
- This is the only time Connor uses his Triassic Ranger powers without the need of Ethan and Kira lending their energy.
- Zeltrax will reappear for the final time in Power Rangers SPD Episode 35.
- This marks the final appearance of Thundersaurus Megazord & Mezodon Megazord which is destroyed.
- The Brachiozord and the rest of the Dinozords weren't destroyed.
- This marks the final appearances of Mesogog, Elsa, Cassidy, Devin, and Anton Mercer.
- This episode marks the destruction of Zeltrax by Tommy and Kira, but he will reappear in "Wormhole".
- The Dino Thunder Rangers would later return to team up with the S.P.D. Rangers in "History" and "Wormhole" while Kira reappears in "Once a Ranger" and Tommy would appear again in "Legendary Battle" and one last time in "Dimensions In Danger " (alongside Trent).
- Part II is the last episode to feature Jason David Frank in the intro.
- Ep. 48: The Final Abare Game - Super Sentai counterpart in Abaranger. See comparison page. (Triassic Ranger last appearance)
- Ep. 49: Break In! Abare Final Decisive Battle - Super Sentai counterpart in Abaranger. See comparison page. (fight footage & story)
- Final Ep.: Only the Abare'd Number - Super Sentai counterpart in Abaranger. See comparison page. (fight footage & story)