Last Hanukkah, a team of undercover private investigators in Israel watched as a former Melbourne school principal accused of child sex abuse hosted her children and grandchildren in her apartment.

Unbeknown to Malka Leifer, the 54-year-old Australian wanted on 74 counts of suspected sexual abuse during her tenure as principal of Adass Israel School in Elsternwick, the investigators were studying her everyday life only 20 metres away - gathering surveillance footage.

Tsafrir Tsachi led the 10 person undercover team in Immanuel, an ultra-Orthodox settlement in the Israeli-occupied West Bank, tracking Leifer’s movements. On Hanukkah, they watched Leifer’s son lighting candles on a menorah, as part of the Hebrew ritual.

The moment is part of over 200 hours of surveillance footage caught over a 10-day period.