DP139: A Faux Oak Finish!

Plot
Ash and friends are pleasantly surprised to hear that Professor Oak will be arriving soon to begin the Twinleaf Town Festival with one of his lectures. Trouble starts brewing, however, as Oak is running late and Team Rocket is taking advantage of that by taking over the lecture with an old plan: to disguise James as the professor to steal Pokemon. Will Ash, Dawn and Brock be able to find him in time to stop Team Rocket? And what do Politoed and Quagsire want with Oak?