Originally the Doctor was on the run from the Time Lords, during the end of the Doctors second regeneration they caught up with him. Because of all the crimes he’d committed, interfering with other cultures they forced him to regenerate and then exiled him to Earth in the 1970′s.
During the Doctors exile he worked for U.N.I.T. With the TARDIS no longer working the Doctor used Bessie to travel about on Earth.
Bessie first appeared in the season 7 story “Doctor Who and the Silurians”. It made its final regular appearance in the fourth Doctor’s first story “Robot”.
Bessie made special appearences in “Robot” (left picture), “The Five Doctors” (Middle picture) and “Battlefield” (Right Picture) with the number plate changed to WHO7
The Whomobile was a low hovercraft type vehicle that was also capable of flying. The car itself was commissioned by Jon Pertwee and was only seen in the 1974 season 11 stories “Invasion of the Dinosaurs” and “Planet of the Spiders”.