Rebecca is getting ready for the upcoming Pilot's Ball but is concerned that Baloo's appearance will let her down. Not wanting to disappoint, Baloo digs out his old tuxedo, but he's gained a fair bit of weight since he last wore it and it no longer fits. Kit suggests Baloo visit the Elizabeth Taper Centre who have some of the strictest weight loss councilors around. Worried that Rebecca might go to the ball with another pilot, he agrees.
Wildcat navigates the Sea Duck to the Elizabeth Taper Centre, but manages to confuse the islands on the map with splatters of guacamole and drops Baloo off at the Thembrian Maximum Security Prison on Bedevilled Island by mistake. Thinking the guards to be the weight loss councillors, Baloo happily complies with every order, but by the time he realises where he really is, it's too late. Fortunately Baloo meets Professor Crackpotkin, an inmate who has managed to build an aeroplane, but Baloo needs to lose ten pounds or it won't get off the ground.
Meanwhile, Kit has also realised where Baloo is and enlists the help of Rebecca and Wildcat to try and save him. On their arrival at Bedevilled Island, they speak with the warden who informs them that Crackpotkin is actually a mad scientist and plans to fly his explosive-filled plane into the Thembrian Gruel Reserve. It's a race against time to save Baloo, but they arrive just in time and manage to rescue him before the plane explodes.
Rebecca is touched that Baloo went to such lengths to impress her and she realises that personality is more important than looks. After several days of dieting however, Baloo is more concerned with eating!