Planet X91 Doorway To Time — mark Stewart

Florian uses the time machine to save Captain Rowark from certain death. After returning to real time she suspects he isn't who he claims to be. Even Josh thinks he might be the alien cannibal, Evelina, even though she died in an earlier explosion. When the proximity alarm begins to scream onboard the Piper Clay, Florian and Josh must band together to get onboard the USS Lock to save it from crashing on planet X91. Flying the Piper into space, the clock is ticking. The only air in the ship is what's in each spacesuit. Josh puts his life on the line when he bravely volunteers to jump from one ship to the next. The act must be done to save the colony. Of course Evelina has other plans.