Plan a: supress all information.

Plan b: deny everything.

Plan c: eliminate all witnesses and evidence.

Plan d: spread around a little misinformation.

Plan e: spread around a little distracting (possibly unbelievable) truth.

Plan f: kill yourself.

Plan g: try to tell the truth; wait for other conspirators to kill you.

Plan h: try to tell the truth; wait to be institutionalized.

Plan i: contact enemy alien faction; defect to their side.

Plan j: start writing your knowledge in the guise of "science fiction."

Plan k: get drunk and stay that way.

Plan l: pray.