half past nine o'clock
`` How can you be sure of that , Mr. Wrandall ? '' asked Smith sharply . The gaunt old face , suddenly very much older than it had been before , took on a stern , defiant expression . `` I spoke with her over the telephone at half past nine o'clock that night , '' said he steadily . Smith was not the only one to be surprised by this startling declaration . Sara Wrandall 's eyes widened ever so slightly , and one might have detected a sharp catch in her breath . `` She called you up ? ''