Underground
Episode: 1x01 | Airdate: Sep 7, 1997
Season 1
Submarine
Episode: 1x02 | Airdate: Sep 14, 1997
Special Effects
Episode: 1x03 | Airdate: Sep 21, 1997
Zoos
Episode: 1x04 | Airdate: Sep 28, 1997
Cool Cars
Episode: 1x05 | Airdate: Oct 5, 1997
Coasters
Episode: 1x06 | Airdate: Oct 12, 1997
Sports
Episode: 1x07 | Airdate: Oct 19, 1997
Garbage
Episode: 1x08 | Airdate: Oct 26, 1997
Boats
Episode: 1x09 | Airdate: Nov 2, 1997
Buildings
Episode: 1x10 | Airdate: Nov 9, 1997
Aircraft Carriers
Episode: 1x11 | Airdate: Nov 16, 1997
Electricity
Episode: 1x12 | Airdate: Nov 23, 1997
Food Production
Episode: 1x13 | Airdate: Nov 30, 1997
Emergency
Episode: 1x14 | Airdate: Dec 7, 1997
Aquariums
Episode: 1x15 | Airdate: Dec 14, 1997
Toys and Games
Episode: 1x16 | Airdate: Dec 21, 1997
Spaceships
Episode: 1x17 | Airdate: Dec 28, 1997
Robots
Episode: 1x18 | Airdate: Jan 4, 1998
Greatest Hits #1
Episode: 1x19 | Airdate: Jan 11, 1998
Money
Episode: 1x20 | Airdate: Jan 18, 1998
Air Transportation
Episode: 1x21 | Airdate: Jan 25, 1998
Music Production
Episode: 1x22 | Airdate: Feb 1, 1998
Fly at Your Own Risk
Episode: 1x23 | Airdate: Feb 8, 1998
Season 2
Fly at Your Own Risk
Episode: 2x01 | Airdate: Feb 8, 1998
North Pole
Episode: 2x02 | Airdate: Sep 6, 1998
Whodunnit!?
Episode: 2x03 | Airdate: Sep 13, 1998
Gross Out
Episode: 2x04 | Airdate: Sep 20, 1998
Ocean Adventures
Episode: 2x05 | Airdate: Sep 27, 1998
Police Force
Episode: 2x06 | Airdate: Oct 4, 1998
Sports: Riding, Gliding and Sliding
Episode: 2x07 | Airdate: Oct 11, 1998
F.X.!
Episode: 2x08 | Airdate: Oct 18, 1998
Earth Power
Episode: 2x09 | Airdate: Oct 25, 1998
Talk to the Animals
Episode: 2x10 | Airdate: Nov 1, 1998
After Dark
Episode: 2x11 | Airdate: Nov 8, 1998
Emergency Rescues
Episode: 2x12 | Airdate: Nov 15, 1998
Under the Big Top
Episode: 2x13 | Airdate: Nov 22, 1998
Zero Gravity
Episode: 2x14 | Airdate: Nov 29, 1998
Swamps and Gators
Episode: 2x15 | Airdate: Dec 6, 1998
Mega Trucks
Episode: 2x16 | Airdate: Dec 13, 1998
Boom!
Episode: 2x17 | Airdate: Dec 20, 1998
The Fastest Cars, Humans and Airplanes
Episode: 2x18 | Airdate: Dec 27, 1998
Greatest Hits #2
Episode: 2x19 | Airdate: Jan 3, 1999
Creepy Crawlers
Episode: 2x20 | Airdate: Jan 10, 1999
Monster Trucks
Episode: 2x21 | Airdate: Jan 17, 1999
How Do They Do That?
Episode: 2x22 | Airdate: Jan 24, 1999
Season 3
Cool Schools
Episode: 3x01 | Airdate: Sep 5, 1999
Ticket to Ride: Awesome Amusements
Episode: 3x02 | Airdate: Sep 12, 1999
Sea Creatures
Episode: 3x03 | Airdate: Sep 19, 1999
Dirty Work
Episode: 3x04 | Airdate: Sep 26, 1999
Slimy and Slithery
Episode: 3x05 | Airdate: Oct 3, 1999
Body Mechanics
Episode: 3x06 | Airdate: Oct 10, 1999
Spook Out
Episode: 3x07 | Airdate: Sep 17, 1999
Super Bikes
Episode: 3x08 | Airdate: Oct 24, 1999
Freaky Flying
Episode: 3x09 | Airdate: Oct 31, 1999
Greatest Hits #3
Episode: 3x10 | Airdate: Nov 7, 1999
Pirates and Gold
Episode: 3x11 | Airdate: Dec 12, 1999
Ice
Episode: 3x12 | Airdate: Nov 21, 1999
Fun in the Desert
Episode: 3x13 | Airdate: Nov 28, 1999
Life Savers
Episode: 3x14 | Airdate: Dec 5, 1999
Down Below
Episode: 3x15 | Airdate: Nov 14, 1999
Navy Seals
Episode: 3x16 | Airdate: Dec 19, 1999
Killer Creatures
Episode: 3x17 | Airdate: Dec 26, 1999
Real Life Science Fiction
Episode: 3x18 | Airdate: Jan 2, 2000
Greatest Hits #4
Episode: 3x19 | Airdate: Jan 9, 2000
Space Station
Episode: 3x20 | Airdate: Jan 16, 2000
Water
Episode: 3x21 | Airdate: Jan 23, 2000
Behind the Scenes at Big Events
Episode: 3x22 | Airdate: Jan 30, 2000
Season 4
X-Treme Rides
Episode: 4x01 | Airdate: Jan 7, 2001
Fighting Disaster
Episode: 4x02 | Airdate: Jan 14, 2001
Escape
Episode: 4x03 | Airdate: Jan 21, 2001
Horse Play
Episode: 4x04 | Airdate: Jan 28, 2001
In Deep Water
Episode: 4x05 | Airdate: Feb 5, 2001
On the Front Lines
Episode: 4x06 | Airdate: Feb 12, 2001