WATCH: Will Adele Make You Gay? Show Exposes 'Ex-Gay' Therapy

Editor's note: This story has been updated to accurately reflect John Smid's role in the documentary.

Don't listen to Adele if you're a gay man who wants to become straight. And don't wear tight underwear either.

Those are among the bizarre bits of advice received by British physician and TV personality Christian Jessen as he explores the world of "ex-gay" therapists in a documentary special airing tonight on the U.K.'s Channel 4.

In the show, titled Cure Me, I'm Gay, most of the therapists Jessen visits are in the United States. He meets with a Dallas man who recommends coloring books as a tool to change clients' sexual orientation and a London minister who offers to exorcise "gay demons," reports London's Daily Star. He also undergoes "aversion therapy," being shown images of nude men while drinking ipecac syrup to induce vomiting. Jessen, who is gay, calls "ex-gay" therapy "a load of utter rubbish."

John Smid, a former ex-gay activist from Texas, demonstrates what his now-defunct therapy program would have done for a client like Jessen: for instance, telling him to throw out his Adele CD, as "Adele is very popular within the gay community." In this mock intake, Smid also cautions Jessen that tight underwear will produce sexual arousal.

Smid came out as gay in 2011 and renounced "ex-gay" therapy, which has been discredited by major mental health organizations and abandoned even by some religion-based practitioners. "Smid himself now admits: 'I've never met a man who experienced a change from homosexual to heterosexual,'" reports London's Daily Mail.

Another London paper, The Telegraph, calls Cure Me, I'm Gay "a compelling, sometimes shocking, film." Its reviewer also writes of Jessen, "His enquiries strike a neat balance between laughing at the absurdity of the theories and highlighting how dangerous they are when levelled at vulnerable people."

The documentary airs at 10 p.m. U.K. time. Watch a trailer below.