誰だっけ

who was it again?

→ 誰
phrase Rare #38,704
who was it again? A casual way to ask when trying to remember or confirm someone's identity. The polite form is 誰でしたっけ.
JA: この人、誰だっけ?
EN: Who was this person again?

誰だっけなあ?

Who was it again?

— Love Letter (1995)

〈誰だっけ…〉

Who was it again…?

— 映画 聲の形 (2016)

誰だっけ

Who was that again?

— 別れる決心 (2022)

誰だっけ?

Who was that again?

— 君の名は。 (2016)