Autoencoder networks, trained only on QCD jets, can be used to search
for anomalies in jet-substructure. We show how, based either on images
or on 4-vectors, they identify jets from decays of arbitrary heavy
resonances. To control the backgrounds and the underlying systematics we
can de-correlate the jet mass using an adversarial network. Such an
adversarial autoencoder allows for a general and at the same time easily
controllable search for new physics. Ideally, it can be trained and
applied to data in the same phase space region, allowing us to
efficiently search for new physics using un-supervised learning.