Roy Lee "Rocky" Dennis (December 4, 1961 – October 4, 1978) was an American teenager who had craniodiaphyseal dysplasia, an extremely rare sclerotic bone disorder.

Over the next year, he visited doctors at University of California, Los Angeles (UCLA)'s medical center multiple times a week, culminating in a diagnosis of craniodiaphyseal dysplasia (CDD), an extremely rare bone disorder that causes bone tissue to build up excessively, including in the skull, causing gradual compression of the brain and thus intracranial hypertension.

[1][3][4][5] Based on the small number of recorded cases — in a 1985 television interview, Rusty said Dennis' doctors told her there were seven recorded cases of CDD[4] — doctors predicted that the pressure from bone accumulation on the central nervous system and cranial nerves would destroy his eyesight and hearing, and eventually affect his brain, anticipating he would die prior to his seventh birthday.

[2][5] In the years following Dennis' diagnosis, he lived with his parents and older half-brother Joshua in Covina and Glendora.

[5] Many of Rusty's biker friends frequented their home, acting as a secondary support system for the family, particularly following Dennis' parents divorce in 1971.

Rusty handed Dennis a book, which he promptly read aloud before telling the doctor, "I don't believe in being blind.

She was successful at campaigning on Dennis' behalf and was able to enroll him in public school, where he was initially academically behind his classmates, but quickly caught up and graduated from Sandburg Junior High as an honor student.

[citation needed] Peter Bogdanovich directed the 1985 film Mask, from Anna Hamilton Phelan's screenplay based on Dennis' life.