It looks like you’re asking about a related to the phrase "Searching for- inside no 9 in-" — possibly a reference to the anthology series Inside No. 9 (by Reece Shearsmith and Steve Pemberton).
If you mean: Not exactly. However, there is an episode “The 12 Days of Christine” (S2E2) that involves fragmented memories and a man repeatedly appearing. There’s also “The Riddle of the Sphinx” (S3E3) involving cryptic crosswords, and “Death Be Not Proud” (S5E5) featuring a search for hidden treasure in a flat. But none is titled “Searching for” . Searching for- inside no 9 in-