So I have watched Interstellar twice now, and each time Doyle has really stood out to me (mainly because he's portrayed by Wes Bentley XD). So here's a little insight on his last moments. Enjoy :D

The wave sends Doyle plummeting into sheer, cold blackness. He can feel the waters iciness through the material of his suit, lapping at every fold and cranny of his clothes, searching for any entrance.

'So this is how it ends,' he thinks calmly. Gravity pulls him firmly down, and with the weight of his suit he knows he will not find a silver lining if he tries to swim.

The words of Professor Brand echo through his mind as he sinks, bringing him a small inkling of comfort.

"Do not go gentle into that good night,
Old age should burn and rave at close of day;
Rage, rage against the dying of the light."

It's strange, Doyle muses, that he has never had a fear of drowning. Somehow, the circumstance never seemed to cross his mind, as the only suffocation that ever concerned him was from the dust in the air.

"Though wise men at their end know dark is right,
Because their words had forked no lightning they
Do not go gentle into that good night.
Good men, the last wave by, crying how bright
Their frail deeds might have danced in a green bay."

As the second wave hits, the force of it sends a thin crack across the front of his helmet. Doyle closes his eyes, inhaling the last few breaths of air he has left. The end is not far now.

"Wild men who caught and sang the sun in flight,
And learn, too late, they grieved it on its way,
Do not go gentle into that good night.
Grave men, near death, who see with blinding sight
Blind eyes could blaze like meteors and be gay,
Rage, rage against the dying of the light."

The third wave completely tears his helmet from his head, exposing his inky black hair to the frigid oceans. Doyle smiles, holding his last breath. He'll be okay. He knows They have found him now.

"And you, my father, there on the sad height,
Curse, bless, me now with your fierce tears, I pray.
Do not go gentle into that good night.
Rage, rage against the dying of the light"