Ace Double (#78400, 75-cent cover price) August 1970 paperback. Condition is VG+: tight and square with flat spine; age tanning is mild and uniform (insides of covers slightly darker); light overall wear (more on the Jakes side.) No stamps, marks, or writing.

An Ace Double from 1970 - containing The Star Virus by Barrington J. Bayley, bound with Mask of Chaos by John Jakes.

The Star Virus by Barrington J. Bayley - (cover by Kelly Freas, frontispiece by Jack Gaughan, 121 pages.) The first novel by this reasonably prolific British author - one I think could be described as "darker" space opera. I read this 30 years ago and liked it, but have to rely now on the sketchy teaser on the first page blurb:
We demand that you hand over the object.
-Impossible. Ownership is in the hands of our clients.
Human ownership of the object is not admissible. Streall claims is absolute. You will notify of whereabouts.
-It is already in transit.
We will intercept. Notify.
-Your claim must be made through the courts.
Human courts mean nothing to the Streall. Either you comply or Streall fleets will occupy the Kantor system.

(Bound with) Mask of Chaos by John Jakes - (cover by Jack Gaughan, 132 pages.) Mike was apprehensive about being stranded on Tome. But the peaceful city and the exquisite masks everyone wore somehow allayed his fears. The sculptured expressions of tranquility and the ghastly, frail smiles lured him into serenity. He soon compared his plight on Tome to a sojourn in Eden - until Mike met a flame-haired woman with an apple. She taught him to see the horror behind the masks, to look beyond what people and things "seem" to be. But then again, he wasn't what he seemed to be. He didn't need a mask. He was a mask...