Dr. McDreamy is a hero on and offscreen and now the actor and avid cyclist is taking aim at a former cycling hero for not fessing up.

In an interview on Thursday Patrick Dempsey tells HLN host Robin Meade he is ready to take on Lance Armstrong: “The best thing he can do is really confess the truth.” Not buying the innocent act, the actor adds, “let everybody know why and how he did it so that we can move on.”

And the “Grey’s Anatomy” star isn’t the only one who doesn’t buy Lance’s story after the athlete was dropped by Nike and he stepped down as chair of Livestrong, the foundation he founded.

Meanwhile, Patrick – also a race car driver in his spare time – is gearing up to take part in a 10-hour endurance sports car road race in Atlanta on Saturday, October 20 named the Petit Le Mans.

Watch the interview below! What’s your take? Do you think there is more for Lance to tell the public?