Is the mysterious airman who tails the Lafayette Escadrille a guardian angel or a bird of prey? Can he be in the pages missing from the flight log of newcomer George S. Dumont, who seems to have a lot on his mind? Or did he materialize on the R.F.C. ferry runs of young Allen Hope, ""practically related"" to Dumont? Easy in the air, clogged along the pipe-lines: a strain on credulity but not on attention.