Dear Mr. Plummer:

I am making a presentation soon on The Sound of Music, and chose it partially due to the attention recently given to it on its 50th anniversary. Although you’re making nice right now, we all know you’ve had a bumpy relationship with the film from the beginning (an understatement, of course). You’ve often tried—unsuccessfully—to distance yourself, and even separate yourself from it. The reason you can’t is that your performance is part of the basis for the film’s success.

Without your performance, The Sound of Music might well have floated away into the clouds or gone even more cotton candy sweet than it did, all effort to diminish that sweetness by director Robert Wise notwithstanding. You grounded the film, sir, in more ways than you might have realized.

First, you kept connected with the film throughout the performance, and your professionalism never let you bring anything less than your “A” game. I may be reading you wrong, but it seemed as if there were moments that you were doing everything you could not to reveal that you thought you were slumming, and that what you were doing was either beneath you or simply Not Your Thing. I know that you and Ms. Andrews were laughing yourselves silly in the “Something Good” sequence with the groaning arc light situation. You seemed to be working extra hard to stay engaged with her when she was singing to you during that number. But you did stay engaged, and the scene was the richer for it.

You also made the most of every scene you were in. As underwritten as the character of the Captain might have been, you made it as real and fleshed out as you could. You added humor, slyness, darkness and depth to almost every scene you were in. If, as you stated, working with Ms. Andrews was like being hit over the head daily with a big Valentine’s Day card, you provided the dark undertone that enabled her to work to define and ground the sweetness into something real and relatable.

As the more accomplished, experienced and talented actor, I can only imagine what you brought to every scene you had with Ms. Andrews. She has given you credit for teaching her how to act angrily in her scene where she is rebuking your character for not paying enough attention to your children (after they have all gotten dunked when the boat tipped over). If that’s the case, you taught her well. Her anger may never have the same edge as yours, it was her own real anger, and it made for a believable, strong scene. You need to be aware of how much you were able to bring out of her as an actress. We’ll never exactly know, of course, but I can only imagine it would have been a much lesser film without your participation, your example, and your spoken and unspoken training of your fellow actors.

You have the reputation of being an underplayer, and it worked well here. But it was what you were underplaying that worked so well. You brought sorrow, pained isolation, and yes, even a current of dark sexuality to the part. Perhaps that is just part of “who you are,” but thanks to your commitment to the part –painful for you or not—you make the part your own and added a depth, weight and darkness it needed. The film is infused with that darkness to some extent, and while generally unnoticed under the mountains, children, nuns, music and the glories of Ms. Andrews’ voice and performance, it’s there.

You weren’t just involved in a wildly successful film musical, Mr. Plummer. You were a great part of its success and its longevity. I hope you’ll soon see that and embrace it.