Robert Downey Jr. and Jimmy Fallon Recall Worst, Unaired 'SNL' Sketches

Andrew Lipovsky/NBC

The two also filmed a segment in which they starred in a '90s-themed allergy medicine commercial and read their lines off of cue cards during Wednesday's episode of 'The Tonight Show.'

Robert Downey Jr. and Jimmy Fallon shared their worst, unaired Saturday Night Live sketches when the actor stopped by The Tonight Show on Wednesday.

Downey, who only worked on SNL for one year when he was 20, said that his time on the show was "arguably the worst season in its history."

He recalled the only sketch that he wrote that made it close to air, which he shared was a "ridiculous sketch called 'Suitcase Boy.'" He explained, "I came out with a suitcase zipped around my neck and said a bunch of non sequiturs. And it was so not funny, except to me and my weirdo friends."

Fallon also shared his worst sketch, which was called "Plate Boy and Cup Boy." He said, "Alec Baldwin was the host and he's always been great to me and he was always like, 'Try new things.'"

The sketch was inspired by Horatio Sanz's ability to shake cups back and forth until they flew "up into the air kind of like a tornado."

Fallon then shared a clip from the unaired sketch, which featured Fallon struggling to carry a pile of paper plates and Sanz's pile of cups flying into the air.

Also during the appearance, Downey and Fallon made a '90s-themed ad for allergy medicine called Zynerma. They did not know what they would say before the sketch and read their lines off of cue cards they saw for the first time while performing.

Fallon opened the segment by standing in a greenscreen field of grass and wearing a voluminous wig. He said that before taking the medicine, his allergies would keep him in bed all day. "Now the only thing keeping me in my bed is my fear of tall men," he said while holding up the medicine's box.

Sporting a blond wig, Downey timidly read the possible side effects, which included "thought blisters, the mumps, hepatitis K, gooberlycosis, tripolar depression and slacks premature fatherhood, stump lung, crispix and hat failure."

"Zynerma shouldn't replace your asthma inhaler and it can't replace her," he actor later said. "Sorry big guy, but she's not coming back. The sooner you accept that, the better off we're all gonna be."

Downey and Fallon then appeared onscreen together. Both turned around to face the camera before the host credited the medicine for helping him live after he was declared legally dead for 15 hours. Downey added, "If your erection lasts more than four hours, that has nothing to do with Zynerma, but congratulations."

"One time I got a Lego man stuck in my nose. I blew and blew and blew, but he wouldn't come out. He's still up there to this day," said Fallon. "Sometimes when I'm lying in bed at night, I think about him. How old he is. If he ever got married. If he's happy. Then the Ambien kicks in and I fall asleep naked in the front yard."

Fallon broke character and began to laugh when both he and Downey missed their cues. Another problem presented itself when Downey's wig shifted on his head, though he continued to read his lines and encouraged the commercial's viewers to try to date their doctors.

The commercial concluded with the two reuniting onscreen. "I lived in the back of a Walgreens for three years because my arm was stuck in the blood pressure machine," said Fallon. Downey explained that he found Fallon and "took him home, hosed him off in his yard and nursed him back to health with Muscle Milk."

After gaining 600 pounds, Fallon went on a long journey to lose the weight and credited his good friend for helping. "After his friend escaped, I stepped in," said Downey.