DWTS: Frankie Muniz doesn't remember starring on 'Malcolm in the Middle'

The theme on Monday’s Dancing with the Stars was “The Most Memorable Year.” But for Frankie Muniz, it’s not such a relatable theme.

Before opening the ABC show with a performance of the quickstep, Muniz revealed in his rehearsal video that he can’t remember most of the things he’s experienced in his life, including his six years on the Fox comedy Malcolm in the Middle. Muniz revealed that he’s suffered nine concussions and several mini-strokes, or transient ischemic attacks, but he can’t say for sure what prevents him from recalling the past, like when he did the sitcom from 2000 to 2006.

“It makes me a little sad,” Muniz said on the show. “Things pop back into my mind [that] I should have remembered.”

The show also included an interview with his former TV dad, Bryan Cranston, who marveled at how much Muniz has experienced in his life. “Frankie was a TV star, then he became a race car driver, and a drummer in a rock band. I said to him once, ‘What are you going to be, an astronaut next? You are doing all the things professionally that everybody dreams about.'”

“I’ve gotten to do anything that I really wanted to do,” Muniz replied. “But the truth is, I don’t really remember much of that.”

He admitted to his partner Witney Carson that he hasn’t gone to doctors about his memory loss. “To be honest, I’ve never really talked about it.”

Cranston said he told Muniz not to worry about what he can’t remember. Cranston starred with Muniz in 151 episodes of Malcolm. “They are still [his] experiences,” Cranston said. “It will me my job, I will tell him, ‘remember this? Remember that on Malcolm?’ What a life for you.”

Muniz went on to earn a 24 out of 30 for his quickstep with Carson. To stay with the Most Memorable Year theme, Muniz said he chose to focus on the present.

“Truth is, I don’t remember much [of my time on Malcolm]” said Muniz, whose girlfriend Paige keeps a daily diary for him. “It almost feels like it wasn’t me.”