Optimize query contains too many inner join and rows

I have the following query

SELECT * 
INTO ##TempStaffT
FROM Staff HF 
WHERE  HF.[businessline_id]='T'
AND HF.[offices_id] IN (SELECT * FROM ##TempParamOffice)
AND HF.[specialism_id]IN (SELECT * FROM ##TempParamSpecialism)
AND HF.[onetouch]IN (SELECT * FROM ##TempParamConsultant)

 SET @sql4 = N'

INSERT INTO ##TempFees(' + @columns1 + ',CALF_AN ,BusinessName)
SELECT distinct ' + @columns2 + ',p.CALF_AN ,CB.[TempBusinessName] as BusinessName
   FROM 
     dbo.WTEFAC EF 
  inner JOIN  dbo.WTFAC F ON EF.EFAC_NUM = F.EFAC_NUM 
  inner JOIN  dbo.WTFACINFO BS ON F.FAC_NUM = BS.FAC_NUM 
  inner JOIN dbo.WTLFAC LF ON F.FAC_NUM = LF.FAC_NUM 
  inner JOIN dbo.WTRUBVARIANTEFAC WRU ON LF.RINT_ID = WRU.RINT_ID 
  inner JOIN dbo.WTACUMFAC WTA ON WRU.RUV_ID = WTA.RUV_ID 
  inner JOIN ##CUM_CODEHT WTA1 ON WTA.CUM_ID = WTA1.CUM_ID 
  inner JOIN dbo.WTVTAT TAT ON BS.TIE_ID = TAT.TIE_ID AND BS.RFAN_ID = TAT.RFAN_ID AND BS.PER_ID = TAT.PER_ID AND BS.CNT_ID = TAT.CNT_ID
  inner JOIN dbo.PYCONTRAT CC ON TAT.PER_ID = CC.PER_ID AND TAT.CNT_ID = CC.CNT_ID 
  inner JOIN dbo.WTMISS M ON CC.PER_ID = M.PER_ID AND CC.CNT_ID = M.CNT_ID 
  inner JOIN dbo.WTCNTI COT1 ON M.PER_ID = COT1.PER_ID AND M.CNT_ID = COT1.CNT_ID
  inner JOIN dbo.WTQUAEU Q ON COT1.TIE_ID = Q.TIE_ID AND COT1.QEU_CDE = Q.QEU_CDE
  inner JOIN dbo.WTSCCT C ON CC.RGPCNT_ID = C.RGPCNT_ID AND CC.PER_ID = C.PER_ID AND CC.CNT_ID = C.CNT_ID --AND''SECT3'' = C.STTQ_COD 
  INNER JOIN ##TempStaffT HF ON C.VAPO_CODE = HF.onetouch  COLLATE Latin1_General_CI_AS
  inner JOIN 
##TempA AS p  ON p.CNT_ID = COT1.CNT_ID  inner JOIN 
 ##TempB AS p1  ON p1.CNT_ID = COT1.CNT_ID
  CROSS JOIN [dbo].[CustBusinessTable] CB
WHERE  CB.[TempBusinessName]=''Pure Temp Fees''

GROUP BY p.CALF_AN,CB.[TempBusinessName]
'
;
PRINT @sql4;

My problem is that the query above took 20 min to be executed because ##TempStaffT contains too many rows , how can I optimize it ? I use many temp tables but it seems not to be worked , Any idea ? Many thanks in advance .