there were two further novels by murray leinster — "the hot spot" and "unknown danger" (pyramid, 1969). the first two leinster books were reprinted in 1969 in the united kingdom by world distributors, the eponymous novel retitled "the trap." unknown danger was not published in the uk, but world distributors also published two united kingdom-only novels the same year, "slingshot for a david" and "the mean city"; both were credited to james bradwell, a pseudonym for arthur william charles kent.