Citroen's C2 is the replacement for the Saxo at the bottom end of the French car manufacturer's range. Based on the same platform as the slightly larger C3 and C3 Pluriel, the C2 is only available as a three-door model because the C3 covers five-door territory.
C2 : Note that the C2 only has three doors (that is, two side doors and the rear hatchback). Reason for that is that its C3 sister model will only comes with five doors (discounting the C3 Pluriel, okay?). Citroen says that the C2 is 'small and dynamic, but comfortable over long journeys.' Just about right.