use inner query query order sequence in outer query result

use inner query query order sequence in outer query result

I have two tables- ALPHA & BETA. I am using the result of a query on BETA
for an outer query on ALPHA.
SELECT a,b FROM alpha WHERE a IN(SELECT a FROM beta WHERE some_condition
ORDER BY c DESC);
Now my problem is that i need to maintain the DESC ORDER in the final
result but since i dont have access to c in table alpha,i am not able to
do display result in desired oder.
Is there any way to use the inner query order sequence in outer query. I
cannot change the structure of either of the tables.