“We’ve stumbled into a very important clue,” Kennedy told her, with a show of giving her his confidence.  “In that bag in Walter’s hand is one of the studio towels.  It contains a hint of the poison used to kill Miss Lamar and—­of utmost consequence—­it has provided me with an infallible clue to the identity of the murderer himself—­or herself.”

It seemed to me that Marilyn blanched.  “Where—­where did you find it?” she demanded, in a very awed voice.

“In one of the studio washrooms.”

“It has been—­it has been in the washroom ever since poor Stella’s death?”

“No, not that!  Jameson discovered it the same day but”—­the very slight pause was perceptible to me; Kennedy hated to lie—­“I haven’t realized its importance until just this morning.”

Enid Faye, seeing us from a distance, conquered her dislike of Marilyn sufficiently to join us.  She was very erect and tense.  Her eyes, wide and sober and searching, traveled from my face to Kennedy’s and back.  Then she dissembled, softening as she came close to me, laying a hand on my shoulder and allowing her skirt to brush my trousers.

“Tell me, Jamie,” she whispered, her warm breath thrilling me through and through.  “Has the wonderful Craig Kennedy discovered something?” It was not sarcasm, but assumed playfulness, masking a throbbing curiosity.

“I found a towel in one of the studio washrooms,” I answered, “and Craig has demonstrated that it is a clue to the poison which killed Stella Lamar as well as to the person who did it.”

Enid gasped.  Then she drew herself up and her eyes narrowed.  Now she faced Kennedy.

“How can the towel be a clue to the crime?” she protested.  “Stella was—­was murdered way out in Tarrytown!  Mr. Jameson found the towel here!”

Kennedy shrugged his shoulders.  “I cannot tell you that—­just yet.”  He paused deliberately.  “You see,” he lied.  “I have yet to make my analysis.”

“But you know it’s a clue to the—­”

“That towel”—­he raised his voice, as though in elation—­“that towel will lead me to the murderer—­infallibly!”

Merle Shirley had come up in time to hear most of the colloquy between Enid and Kennedy.  At the last he flushed, clenching his fists.

“If you can prove who the murderer is, Mr. Kennedy,” he exploded, “why don’t you apprehend him before some one else meets the fate of Werner?”

“I can do nothing until I return to my laboratory this afternoon.  I will not know the identity of the guilty person until I complete a chemical analysis.”