Aliens exist, says former emergency medical physician Steven Greer, and he thinks he has the evidence to prove it - including a 6-inch body he believes is a visitor heralding from a distant planet.

This, among other forms of evidence, including alleged government documents, photographs, audio and "high-level witness" testimony, is scheduled for release in the documentary "Sirius" on April 22.

The purpose of the film, however, isn't only to offer what those behind it believe to be convincing evidence that extraterrestrials exist and have visited Earth, but rather what they see as the politically- and financially-driven conspiracy to cover it up.

"What people need to understand is the secrecy around UFOs and extraterrestrial intelligence really has nothing to do with ETs," Greer said in a video statement. "It has to do with humans and the power that is resting in large corporations and financial interests that do not want you to know the truth."

These interests, Greer and his colleagues believe, rest largely in energy corporations who fear the technology out-of-town visitors are using to reach our planet - a technology, Greer said, humans have already acheived but is kept hidden away.

"Once people understand that classified projects have figured out how UFOs operate, they will realize we no longer need oil, coal and nuclear power," he said. "This is the truth that has driven the secrecy."

In the meantime, the very lack of these technologies are what Greer believes is "driving the planet into ground."

In all, the movie's release, which has long since sold out, marks for Greer and his colleagues the point when they stop waiting for the government to do something about the supposed proof, and transfer it to the hands of the masses.

And nor is he alone. Overseeing the film is the Emmy Award-winning director Amardeep Kaleka who said he offered his help because he felt the group was working on "groundbreaking ideas over the past decade and pushing a truth that either not a lot of people know about, or are scared to discuss."