Reynolds hid his identity with large unicorn mask and glittery rainbow cape. He sang a very sweet, very honest rendition of "Tomorrow" from Annie.
Recently, Reynolds stopped by Variety to chat about his work on Deadpool 2 at the film's Los Angeles premiere.
When asked by the host if he was nervous during the performance, Reynolds quipped: "Yes, absolutely".
Based around the concept of celebrities singing while disguised, Masked Singer featured a performer known only as "Unicorn" during the most recent episode.
We know Deadpool wears a mask, and normally we would not encourage studios to promote a Ryan Reynolds movie by hiding his face, but this was clearly a flawless promotional appearance.
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Among those present were delegates from Guatemala and Paraguay, which will open their own Jerusalem embassies later this month. The Trump administration has said the final boundaries of Jerusalem would be left up to final status negotiations.
Below is Reynolds' song and the following video showcases his reveal to the contestants. "I was wearing an adult diaper!"
Then, suddenly, they reveal themselves to be one of the biggest movies stars in the entire world!
Honestly, even though he declared himself "in the top five worst singers in the universe", we were kind of impressed with Reynolds' pipes.
"Thank you guys for having me", Reynolds said.
Deadpool 2 has also received glowing early reviews with some critics calling it even better than the original.
Catch Reynolds in Deadpool 2, which hits theaters on May 18 in the US, May 15 in the United Kingdom and May 16 in Australia.