Dennis Dragons were firstly introduced by Kowloon Motor Bus ("KMB") in 1982. Three 12-metre prototypes (3N1-3) were provided by Dennis Specialist Vehicles for evaluation purpose. These 3 buses were fitted with Alexander R-type bodies, which were also the first 3 buses fitted with this type of body in the fleet. "Dragon" is only the name for the 3-axle version of Dominator ordered by KMB, which is substantially the same as the "Condor" of China Motor Bus. Later, "Dragon" became the standard name for 3-axle Dominator and Dragons were also ordered by Citybus, HACTL, and some other African countries.
KMB was satisfied with the performance of the 3 prototypes and finally ordered 188 more 12-metre Dennis Dragons (3N4-191). However, the body chosen was of 3-door Duple Metsec for those buses. Therefore 3N1-3 were the only Dennis Dragons with Alexander R-type bodies.
The 3 prototypes have now been withdrawn from passenger service. 3N1 and 3N3 was transferred to the KMB training school as training buses, while 3N2 was scrapped in 2000.