The star passed away in Clearwater, Florida, after being diagnosed with cancer. Leading the tributes to McMahon was Hollywood icon Nicolas Cage, who described him as "kind and intelligent" after the pair shared the screen in this year’s The Surfer.

McMahon was known for portraying villain Doctor Doom in 2005's Fantastic Four and the 2007's sequel, Fantastic Four: Rise of the Silver Surfer. He also played Christian Troy in Ryan Murphy's Nip/Tuck and Cole Turner in Charmed. His more recent credits were in The Residence and The Surfer.

He played the half-human, half-demon Cole Turner in the WB supernatural series “Charmed” and a self-destructive playboy in the FX series “Nip/Tuck.”