The second of two appearances in the series by Arnold Diamond, the first being in E6, You Can't Die Twice (1959).
The second of three uncredited appearances in the series by Mary Maxfield, the others being E12, The Chinese Mask (1959) and E39 The Absent Assassin (1960).
The last of three uncredited appearances in the series by Pat Ryan, the others being E12, The Chinese Mask (1959) and E25 Fingers of Guilt (1960).
The second of two appearances in the series by Cyril Shaps, the first being in E13, Slave Ship (1959).
The character Artigas originally appeared in E24, Checkmate (1960). That time he was played by Arnold Bell.