<Tr> <Th_colspan="2"> Doug Ross </Th> </Tr> <Tr> <Td_colspan="2"> George Clooney as Doug Ross </Td> </Tr> <Tr> <Th> First appearance </Th> <Td> September 19, 1994 (1x01, "24 Hours") </Td> </Tr> <Tr> <Th> Last appearance </Th> <Td> March 12, 2009 (15x19, "Old Times") </Td> </Tr>

When does doug ross come back to er