The City Beach resident joins Connor Delves, of Inglewood, as Dalmatian and German prisoners respectively in Capturing the Enemy.
Capturing the Enemy is based in the time when the Department of Defence commandeered Rottnest Island for use as a Prisoner of War camp.
"I came here as a kid and still get that sense of wonder," McInnes said.
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READ NOW"The island is beautiful, I love the natural aspects."
McInnes, in his second year with Scooplight Theatre that presents the annual Rottnest After Dark series, said the play really got to the core of what happened on Rottnest Island during World War I.
"If you look deep enough into it there's a connection with modern-day stuff like the asylum seekers being trapped by Australia," he said.
Delves, who is on summer break following his first year at the American Academy of Dramatic Arts in New York, said the show told stories about people held prisoner on Rottnest Island during the war.
He plays a German prisoner who documents his time on the island through photography.
The theatrical performance marks the centenary of the Great War and the impact it had on the island during 1914 and 1915.