<P> Chicago Med is an American medical drama that premiered on NBC on November 17, 2015 . The series is focused on the emergency department of Gaffney Chicago Medical Center and on its doctors and nurses as they work to save patients' lives . </P> <P> As of October 24, 2018, 66 episodes of Chicago Med have aired . </P> <Table> <Tr> <Th_colspan="2"> Season </Th> <Th_colspan="2"> Episodes </Th> <Th_colspan="2"> Originally aired </Th> <Th_colspan="2"> Nielsen Ratings </Th> </Tr> <Tr> <Th> First aired </Th> <Th> Last aired </Th> <Th> Rank </Th> <Th> Average viewers (million) </Th> </Tr> <Tr> <Td> </Td> <Td_colspan="3"> Pilot </Td> <Td_colspan="2"> April 7, 2015 (2015 - 04 - 07) </Td> <Td> N / A </Td> <Td> 8.43 </Td> </Tr> <Tr> <Td> </Td> <Td_colspan="1"> </Td> <Td_colspan="2"> 18 </Td> <Td_colspan="1"> November 17, 2015 (2015 - 11 - 17) </Td> <Td> May 17, 2016 (2016 - 05 - 17) </Td> <Td> 37 </Td> <Td> 9.83 </Td> </Tr> <Tr> <Td> </Td> <Td_colspan="1"> </Td> <Td_colspan="2"> 23 </Td> <Td_colspan="1"> September 22, 2016 (2016 - 09 - 22) </Td> <Td> May 11, 2017 (2017 - 05 - 11) </Td> <Td> 28 </Td> <Td> 9.47 </Td> </Tr> <Tr> <Td> </Td> <Td_colspan="1"> </Td> <Td_colspan="2"> 20 </Td> <Td_colspan="1"> November 21, 2017 (2017 - 11 - 21) </Td> <Td> May 15, 2018 (2018 - 05 - 15) </Td> <Td> 27 </Td> <Td> 10.10 </Td> </Tr> <Tr> <Td> </Td> <Td_colspan="1"> </Td> <Td_colspan="2"> TBA </Td> <Td_colspan="1"> September 26, 2018 (2018 - 09 - 26) </Td> <Td> TBA </Td> <Td> TBA </Td> <Td> TBA </Td> </Tr> </Table> <Tr> <Th_colspan="2"> Season </Th> <Th_colspan="2"> Episodes </Th> <Th_colspan="2"> Originally aired </Th> <Th_colspan="2"> Nielsen Ratings </Th> </Tr>

How many episodes in chicago med season 4
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