Fantastic Four (1961 1st Series) #181...Published Apr 1977 by Marvel

"Side by Side with...Annihilus?" Guest-starring Tigra and Thundra. Written by Roy Thomas. Pencils by Ron Wilson. Inks by Joe Sinnott. Cover by Jack Kirby and Joe Sinnott. After a one-issue hiatus, Reed Richards' odyssey into the Negative Zone continues! When Annihilus appears, Reed prepares for the worst, but the FF's old foe just wants to ask Mr. Fantastic for help. Meanwhile back at the Baxter Building, the Invisible Girl is certain that the Counter-Earth Reed Richards is posing as her husband. So she goes to Alicia's place...just in time to watch Agatha Harkness take off with young Franklin! How many crises can the FF handle? Cameo appearances by the Mad Thinker and Frankie Raye. Note: This issue concludes Roy Thomas' 2-year stint as the writer for the Fantastic Four series