Three Weeks
Written by
W. E. Johns
Copyright 1933
10th of 13 stories in . It was published in Popular Flying Magazine, April 1934. It was republished as Marooned by Biggles in The Modern Boy #382, Jun. 1, 1935.
Biggles must come up with a clever ploy to keep a Russian spy named Ivan Nikitoff from being able to pass along vital intel.