Inside front cover featuring scenes from interior stories with graytones and touch-ups by Marie Severin.
Story in 3 parts:: Part 1 (5 pp.), Part 2 Trapped in Another World! (5 pp.) & Part 3 The End of Zemu! (3 pp.).
Part 2 of 3. 1st appearances of Zemu, Valeria, Phineas & Theos.
Part 3 of 3. Zemu, Valeria & Phineas would return in Fantastic Four #158 (May 1975).