[2] After unexpectedly winning the lead role in a play his freshman year, however, he enrolled in a summer acting program at William Esper Studio in New York City, where a teacher encouraged Ettinger to transfer to the Mason Gross School of the Arts at Rutgers University in New Brunswick, New Jersey.

This brought him considerable critical notice, with Dan Seddon of NME noting, "Actor Philip Ettinger (among the series' supporting players) makes a case for himself too, whose stint as the college-aged twins during flashbacks is a raw and fascinating portrayal of the Birdseys complicated youth.

"[7] Vanity Fair's Richard Lawson examined Ettinger and star Ruffalo's collaboration on the twins with favor, "The relationship between Dom and Thomas is drawn with aching clarity, one brother trying to be good to the other while resentments build up around them.

[10][11][12] In it, Ettinger depicts a young nursing home aide struggling to support himself, and his grandparents, in economically depressed Appalachia, by buying excess pain meds from members of his West Virginian community, and reselling them to others in that same area.

Ettinger also stars alongside Emmy-winner Martha Plimpton in Sardinia, a 2024 short film written and directed by Paul Kowalski and Executive Produced by Patton Oswalt.

[17][better source needed] The film is about a serious man trying to avoid catching a deadly laughing plague in a growingly polarized and dystopian society, and was named a 2025 Oscar contender for Best Live Action Short by Deadline.