diff --git a/crates/polars-core/src/chunked_array/ops/mod.rs b/crates/polars-core/src/chunked_array/ops/mod.rs
index 7450735fd312..a3e7f04cc9e1 100644
--- a/crates/polars-core/src/chunked_array/ops/mod.rs
+++ b/crates/polars-core/src/chunked_array/ops/mod.rs
@@ -34,7 +34,6 @@ pub(crate) mod nulls;
 mod reverse;
 #[cfg(feature = "rolling_window")]
 pub(crate) mod rolling_window;
-mod search;
 pub mod search_sorted;
 mod set;
 mod shift;
@@ -238,12 +237,6 @@ pub trait ChunkApply<'a, T> {
         F: Fn(Option<T>, &S) -> S;
 }
 
-/// Search for an item.
-pub trait ChunkSearch<'a, T> {
-    /// Return the index of the given value within self, or `None` if not found.
-    fn index_of(&'a self, value: Option<T>) -> Option<usize>;
-}
-
 /// Aggregation operations.
 pub trait ChunkAgg<T> {
     /// Aggregate the sum of the ChunkedArray.
diff --git a/crates/polars-ops/src/series/ops/mod.rs b/crates/polars-ops/src/series/ops/mod.rs
index b684815238f7..1e1123d77d30 100644
--- a/crates/polars-ops/src/series/ops/mod.rs
+++ b/crates/polars-ops/src/series/ops/mod.rs
@@ -53,6 +53,8 @@ mod rle;
 mod rolling;
 #[cfg(feature = "round_series")]
 mod round;
+// TODO add a feature?
+mod search;
 #[cfg(feature = "search_sorted")]
 mod search_sorted;
 #[cfg(feature = "to_dummies")]
diff --git a/crates/polars-ops/src/series/ops/search.rs b/crates/polars-ops/src/series/ops/search.rs
new file mode 100644
index 000000000000..a5249e1107a3
--- /dev/null
+++ b/crates/polars-ops/src/series/ops/search.rs
@@ -0,0 +1,77 @@
+use polars_core::downcast_as_macro_arg_physical;
+use polars_core::prelude::*;
+use polars_utils::float::IsFloat;
+
+use crate::series::ops::SeriesSealed;
+
+/// Search for an item, typically in a ChunkedArray.
+pub trait ChunkSearch<'a, T> {
+    /// Return the index of the given value within self, or `None` if not found.
+    fn index_of(&'a self, value: Option<T>) -> Option<usize>;
+}
+
+
+impl<'a, T> ChunkSearch<'a, T::Native> for ChunkedArray<T>
+where
+    T: PolarsNumericType,
+{
+    fn index_of(&'a self, value: Option<T::Native>) -> Option<usize> {
+        // A NaN is never equal to anything, including itself. But we still want
+        // to be able to search for NaNs, so we handle them specially.
+        if value.map(|v| v.is_nan()) == Some(true) {
+            return self
+                .iter()
+                .position(|opt_val| opt_val.map(|v| v.is_nan()) == Some(true));
+        }
+
+        self.iter().position(|opt_val| opt_val == value)
+    }
+}
+
+/// Try casting the value to the correct type, then call index_of().
+macro_rules! try_index_of_numeric_ca {
+    ($ca:expr, $value:expr) => {{
+        let ca = $ca;
+        let cast_value = $value.map(|v| AnyValue::from(v).strict_cast(ca.dtype()));
+        if cast_value == Some(None) {
+            // We can can't cast the searched-for value to a valid data point
+            // within the dtype of the Series we're searching, which means we
+            // will never find that value.
+            None
+        } else {
+            let cast_value = cast_value.flatten();
+            ca.index_of(cast_value.map(|v| v.extract().unwrap()))
+        }
+    }};
+}
+
+pub trait SearchSeries: SeriesSealed {
+    fn index_of(&self, value_series: &Series) -> PolarsResult<Option<usize>> {
+        let series = self.as_series();
+        let value_series = if value_series.dtype().is_null() {
+            // Should be able to cast null dtype to anything, so cast it to dtype of
+            // Series we're searching.
+            &value_series.cast(series.dtype())?
+        } else {
+            value_series
+        };
+        let value_dtype = value_series.dtype();
+
+        if value_dtype.is_signed_integer() {
+            let value = value_series.cast(&DataType::Int64)?.i64().unwrap().get(0);
+            let result = downcast_as_macro_arg_physical!(series, try_index_of_numeric_ca, value);
+            return Ok(result);
+        }
+        if value_dtype.is_unsigned_integer() {
+            let value = value_series.cast(&DataType::UInt64)?.u64().unwrap().get(0);
+            return Ok(downcast_as_macro_arg_physical!(series, try_index_of_numeric_ca, value));
+        }
+        if value_dtype.is_float() {
+            let value = value_series.cast(&DataType::Float64)?.f64().unwrap().get(0);
+            return Ok(downcast_as_macro_arg_physical!(series, try_index_of_numeric_ca, value));
+        }
+        // At this point we're done handling integers and floats.
+        unimplemented!("TODO")
+    }
+}
+
diff --git a/crates/polars-python/src/series/scatter.rs b/crates/polars-python/src/series/scatter.rs
index 284b90368158..2fa6a0f729bc 100644
--- a/crates/polars-python/src/series/scatter.rs
+++ b/crates/polars-python/src/series/scatter.rs
@@ -150,64 +150,3 @@ impl PySeries {
         index_of(&self.series, &value.series).map_err(|e| PyErr::from(PyPolarsErr::from(e)))
     }
 }
-
-/// Try casting the value to the correct type, then call index_of().
-macro_rules! try_index_of {
-    ($self:expr, $value:expr) => {{
-        let cast_value = $value.map(|v| AnyValue::from(v).strict_cast($self.dtype()));
-        if cast_value == Some(None) {
-            // We can can't cast the searched-for value to a valid data point
-            // within the dtype of the Series we're searching, which means we
-            // will never find that value.
-            None
-        } else {
-            let cast_value = cast_value.flatten();
-            $self.index_of(cast_value.map(|v| v.extract().unwrap()))
-        }
-    }};
-}
-
-fn index_of(series: &Series, value_series: &Series) -> PolarsResult<Option<usize>> {
-    let value_series = if value_series.dtype().is_null() {
-        // Should be able to cast null dtype to anything, so cast it to dtype of
-        // Series we're searching.
-        &value_series.cast(series.dtype())?
-    } else {
-        value_series
-    };
-    let value_dtype = value_series.dtype();
-
-    if value_dtype.is_signed_integer() {
-        let value = value_series.cast(&DataType::Int64)?.i64().unwrap().get(0);
-        return Ok(downcast_as_macro_arg_physical!(series, try_index_of, value));
-    }
-    if value_dtype.is_unsigned_integer() {
-        let value = value_series.cast(&DataType::UInt64)?.u64().unwrap().get(0);
-        return Ok(downcast_as_macro_arg_physical!(series, try_index_of, value));
-    }
-    if value_dtype.is_float() {
-        let value = value_series.cast(&DataType::Float64)?.f64().unwrap().get(0);
-        return Ok(downcast_as_macro_arg_physical!(series, try_index_of, value));
-    }
-    // At this point we're done handling integers and floats.
-    match value_series.dtype() {
-        DataType::List(_) => {
-            let value = value_series
-                .list()
-                .unwrap()
-                .get(0)
-                .map(|arr| Series::from_arrow("".into(), arr).unwrap());
-            Ok(series.list()?.index_of(value.as_ref()))
-        },
-        #[cfg(feature="dtype-array")]
-        DataType::Array(_, _) => {
-            let value = value_series
-                .array()
-                .unwrap()
-                .get(0)
-                .map(|arr| Series::from_arrow("".into(), arr).unwrap());
-            Ok(series.array()?.index_of(value.as_ref()))
-        },
-        _ => unimplemented!("TODO"),
-    }
-}