26/21a On any old night you hear such an alibi might be airtight (8 or 4-4) Iron C?A?
I got an answer for this already (cast iron) but 14d I think is Hasta la Pasta ( a buzzword in Spaghetti Westerns) so iron C?A?? iron clad.
Many thanks
www.merriam-webster.com/dictionary/ironclad
Examples of IRONCLAD. The company has an ironclad policy against revealing secrets to competitors. He has an ironclad alibi.
13a Epic
14d Pasta
26d and 21a On any old night, you hear, such an alibi might be airtight (8, or 4,4) I??? ??a?. I am getting the I from 25a Holy God! left his book in the hotel (6) Gideon